Sm3+ as effective deactivator for enhanced ∼3 µm laser emission in Er,Sm:SrLaAlO4 crystal.

A promising mid-infrared (MIR) laser crystal with Er, Sm co-doped SrLaAlO4 (Er,Sm:SLA) crystal was successfully grown using the Czochralski (CZ) method. It was the first time that co-doped Sm3+ ion as deactivator for Er3+ activated âˆ¼ 3.0 µm laser. The crystal structure, absorption spectra, emission spectra, and energy level lifetime were discussed in detail. The band structure and density of states were calculated by the density functional theory. The spectral parameters were calculated using Judd-Ofelt (J-O) theory and the deactivate effect of Sm3+ was systematically studied. The introduction of Sm3+ ions enhance the 2.7 µm mid infrared emission intensity by three times, and decrease the lifetime of 4I13/2 energy level of Er3+ ion from 4.35 ms to 0.98 ms. The lifetime ratio of upper and lower levels for 2.7 µm emission was calculated to be 0.63, which is 2.6 times of Er:SLA crystal and comparable to some commercial crystals. All the results indicate that the Sm3+ ion is an effective deactivator for âˆ¼3 µm laser emission. The long upper level lifetime, as well as the large lifetime ratio, the broadening spectra characteristics and the appropriate emission cross-section show the Er,Sm:SLA crystal a good gain material for ultrafast and tunable lasers at âˆ¼3.0 µm.

Potential SLA Hp-4.0 haplotype-restricted CTL epitopes identified from the membrane protein of PRRSV induce cell immune responses.

Swine leukocyte antigen (SLA) class I molecule-restricted T-cell epitopes, which induce cytotoxic T lymphocyte (CTL) responses, play a critical role in the clearance of porcine reproductive and respiratory syndrome virus (PRRSV) and the development of efficient protective vaccines. The SLA-1*04:01:01, SLA-2*04:01, and SLA-3*04:01 alleles, assigned the Hp-4.0 haplotype, are highly prevalent and usually present in all pig breeds. However, the SLA Hp-4.0 haplotype-restricted CTL epitopes in the structural membrane (M) protein of PRRSV are still unknown. In this study, we predicted 27 possible 9-mer epitope peptides in M protein with high binding scores for SLA-1*04:01:01 using CTL epitope prediction tools. In total, 45 SLA class I complexes, comprising the predicted peptide, extracellular region of the SLA-I molecules, and ß2-microglobulin, were constructed in vitro to detect the specific binding of these peptides to SLA-1*04:01:01 (27 complexes), SLA-2*04:01 (9 complexes), and SLA-3*04:01 (9 complexes), respectively. Our results showed that the M27 (T91WKFITSRC), M39 (N130HAFVVRRP), and M49 (G158RKAVKQGV) peptides bind specifically to SLA-1*04:01:01, SLA-2*04:01, and SLA-3*04:01, respectively. Subsequently, using peripheral blood mononuclear cells (PBMCs) isolated from the homozygous Hp-4.0 and Hp-26.0 haplotype piglets vaccinated with commercial PRRSV HuN4-F112 strain, we determined the capacities of these 27 potential peptides to stimulate their proliferation with a Cell Counting Kit-8 and their secretion and expression of interferon gamma (IFN-γ) with an ELISpot assay and real-time qPCR, respectively. The immunological activities of M27, M39, and M49 were therefore confirmed when they efficiently induced PBMC proliferation and IFN-γ secretion in PBMCs from piglets with the prevalent SLA Hp-4.0 haplotype. The amino acid sequence alignment revealed that M27, M39, and M49 are highly conserved among 248 genotype II PRRSV strains collected between 1998 and 2019. These findings contribute to the understanding of the mechanisms of cell-mediated immune responses to PRRSV. Our study also provides a novel strategy for identifying and confirming potential SLA haplotype-restricted CTL epitopes that could be used to develop novel peptide-based vaccines against swine diseases.

Solidification of deep eutectic solvent containing fimasartan through wet impregnation and exploration of flow attributes by modified SeDeM-SLA expert system.

The solidification of deep eutectic solvent (DES) through wet impregnation techniques on inert solid carriers is an interesting approach that offers better processing attributes and excellent stability. Herein, DES of Fimasartan (FS) was developed to improve its solubility and bioavailability. The selected DES-FS was solidified by wet impregnation method employing Nesulin US2 and Aerosil 200. The SeDeM-SLA (solid-liquid adsorption) system was employed to investigate flow attributes of solidified DES-FS. Further, the selected solidified DES-FS (A) was characterized by Fourier transforms infrared spectroscopy (FTIR), Powder X-ray diffraction (PXRD), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM). The DES comprising Choline Chloride (ChCl): Glycerol (Gly) (1:3) revealed maximum drug solubility (35.6 ± 2.2 mg/mL) and thus opted for solidification. Solidification through wet impregnation was employed using 1:0.5 ratios (DES-FS to carriers). The Index of Good Flow (IGF) value was calculated from the SeDeM-SLA expert system, which indicates the better flow characteristics of solidified DES-FS, particularly with Neusilin US2 [SDES-FS (A)]. The solid-state evaluation data of SDS-FS (A) suggested a transition of FS to an amorphous form, resulting in an increment in solubility and dissolution. A similar trend was reported in the in vivo pharmacokinetic study, which indicated a 2.9 folds increment in the oral bioavailability of FS. Furthermore, excellent stability, i.e., a shelf life of 28.44 months, reported by SDES-FS (A) in accelerated stability studies, suggests better formulation perspectives. In a nutshell, the present study evokes the potentiality of performing solidification through wet impregnation and successful implementation of the SeDeM-SLA expert model, which could find wide applications in pharmaceutical science.

Non-Classical Swine Leukocyte Antigens SLA-6, -7, and -8, Are Xenoantigens for Some Waitlisted Patients.

Attack of donor tissues by pre-formed anti-pig antibodies is well known to cause graft failure in xenotransplantation. Genetic engineering of porcine donors to eliminate targets of these pre-formed antibodies coupled with advances in immunosuppressive medicines have now made it possible to achieve extended survival in the pre-clinical pig-to-non-human primate model. Despite these improvements, antibodies remain a risk over the lifetime of the transplant, and many patients continue to have pre-formed donor-specific antibodies even to highly engineered pigs. While therapeutics exist that can help mitigate the detrimental effects of antibodies, they act broadly potentially dampening beneficial immunity. Identifying additional xenoantigens may enable more targeted approaches, such as gene editing, to overcome these challenges by further eliminating antibody targets on donor tissue. Because we have found that classical class I swine leukocyte antigens are targets of human antibodies, we now examine whether related pig proteins may also be targeted by human antibodies. We show here that non-classical class I swine leukocyte proteins (SLA-6, -7, -8) can be expressed at the surface of mammalian cells and act as antibody targets.

JEV infection leads to dysfunction of lysosome by downregulating the expression of LAMP1 and LAMP2.

Japanese Encephalitis Virus (JEV), the predominant cause of viral encephalitis in many Asian countries, affects approximately 68,000 people annually. Lysosomes are dynamic structures that regulate cellular metabolism by mediating lysosomal biogenesis and autophagy. Here, we showed that lysosome-associated membrane protein 1 (LAMP1) and LAMP2 were downregulated in cells after JEV infection, resulting in a decrease in the quantity of acidified lysosomes and impaired lysosomal catabolism. What's more, JEV nonstructural protein 4B plays key roles in the reduction of LAMP1/2 via the autophagy-lysosome pathway. JEV NS4B also promoted abnormal aggregation of SLA-DR, an important component of the swine MHC-II molecule family involved in antigen presentation and CD4+ cell activation initiation. Mechanistically, NS4B localized to the ER during JEV infection and interacted with GRP78, leading to the activation of ER stress-mediated autophagy. The 131-204 amino acid (aa) region of NS4B is essential for autophagy induction and LAMP1/2 reduction. In summary, our findings reveal a novel pathway by which JEV induces autophagy and disrupts lysosomal function.

The Effect of Build Angle and Artificial Aging on the Accuracy of SLA- and DLP-Printed Occlusal Devices.

The aim of this study is to investigate the influence of printing material, build angle, and artificial aging on the accuracy of SLA- and DLP-printed occlusal devices in comparison to each other and to subtractively manufactured devices. A total of 192 occlusal devices were manufactured by one SLA-printing and two DLP-printing methods in 5 different build angles as well as milling. The specimens were scanned and superimposed to their initial CAD data and each other to obtain trueness and precision data values. A second series of scans were performed after the specimens underwent an artificial aging simulation by thermocycling. Again, trueness and precision were investigated, and pre- and post-aging values were compared. A statistically significant influence was found for all main effects: manufacturing method, build angle, and thermocycling, confirmed by two-way ANOVA. Regarding trueness, overall tendency indicated that subtractively manufactured splints were more accurate than the 3D-printed, with mean deviation values around ±0.15 mm, followed by the DLP1 group, with ±0.25 mm at 0 degree build angle. Within the additive manufacturing methods, DLP splints had significantly higher trueness for all build angles compared to SLA, which had the highest mean deviation values, with ±0.32 mm being the truest to the original CAD file. Regarding precision, subtractive manufacturing showed better accuracy than additive manufacturing. The artificial aging demonstrated a significant influence on the dimensional accuracy of only SLA-printed splints.

Assessing the suitability of fused deposition modeling to produce acrylic removable denture bases.

OBJECTIVE: To study the feasibility of using poly methyl methacrylate (PMMA) filament and fused deposition modeling (FDM) to manufacture denture bases via the development of a study that considers both conventional and additive-based manufacturing techniques. MATERIALS AND METHODS: Five sample groups were compared: heat and cold cured acrylic resins, CAD/CAM milled PMMA, 3D-printed PMMA (via FDM), and 3D-printed methacrylate resin (via stereolithography, SLA). All groups were subjected to mechanical testing (flexural strength, impact strength, and hardness), water sorption and solubility tests, a tooth bonding test, microbiological assessment, and accuracy of fit measurements. The performance of sample groups was referred to ISO 20795-1 and ISO/TS 19736. The data was analyzed using one-way ANOVA. RESULTS: Samples manufactured using FDM performed within ISO specifications for mechanical testing, water sorption, and solubility tests. However, the FDM group failed to achieve the ISO requirements for the tooth bonding test. FDM samples presented a rough surface finish which could ultimately encourage an undesirable high level of microbial adhesion. For accuracy of fit, FDM samples showed a lower degree of accuracy than existing materials. CONCLUSIONS: Although FDM samples were a cost-effective option and were able to be quickly manufactured in a reproducible manner, the results demonstrated that current recommended testing regimes for conventionally manufactured denture-based polymers are not directly applicable to additive-manufactured denture base polymers. Therefore, new standards should be developed to ensure the correct implementation of additive manufacturing techniques within denture-based fabrication workflow.

Porcine reproductive and respiratory syndrome virus nsp4-mediated ß2M downregulation contributes to SLA-I decrease and virus infection in vivo and in vitro.

Porcine reproductive and respiratory syndrome virus (PRRSV) infection inhibits swine leukocyte antigen class I (SLA-I) expression in pigs, resulting in inefficient antigen presentation and subsequent low levels of cellular PRRSV-specific immunity as well as persistent viremia. We previously observed that the non-structural protein 4 (nsp4) of PRRSV contributed to inhibition of the ß2-microglobulin (ß2M) and SLA-I expression in cells. Here, we constructed a series of nsp4 mutants with different combination of amino acid mutations to attenuate the inhibitory effect of nsp4 on ß2M and SLA-I expression. Almost all nsp4 mutants exogenously expressed in cells showed an attenuated effect on inhibition of ß2M and SLA-I expression, but the recombinant PRRSV harboring these nsp4 mutants failed to be rescued with exception of the rPRRSV-nsp4-mut10 harboring three amino acid mutations. However, infection of rPRRSV-nsp4-mut10 not only enhanced ß2M and SLA-I expression in both cells and pigs but also promoted the DCs to active the CD3+CD8+T lymphocytes more efficiently, as compared with its parental PRRSV (rPRRVS-nsp4-wt). These data suggested that the inhibition of nsp4-mediated ß2M downregulation improved ß2M/SLA-I expression in pigs.

Late graft failure of pig-to-rhesus renal xenografts has features of glomerulopathy and recipients have anti-swine leukocyte antigen class I and class II antibodies.

Prolonged survival in preclinical renal xenotransplantation demonstrates that early antibody mediated rejection (AMR) can be overcome. It is now critical to evaluate and understand the pathobiology of late graft failure and devise new means to improve post xenograft outcomes. In renal allotransplantation the most common cause of late renal graft failure is transplant glomerulopathy-largely due to anti-donor MHC antibodies, particularly anti-HLA DQ antibodies. We evaluated the pig renal xenograft pathology of four long-surviving (>300 days) rhesus monkeys. We also evaluated the terminal serum for the presence of anti-SLA class I and specifically anti-SLA DQ antibodies. All four recipients had transplant glomerulopathy and expressed anti-SLA DQ antibodies. In one recipient tested for anti-SLA I antibodies, the recipient had antibodies specifically reacting with two of three SLA I alleles tested. These results suggest that similar to allotransplantation, anti-MHC antibodies, particularly anti-SLA DQ, may be a barrier to improved long-term xenograft outcomes.

Development of inert coatings to prevent drug retention in 3D-printed diffusion cells.

Diffusion cells play a crucial role in the pharmaceutical and cosmetic fields by assessing the release and permeation of active pharmaceutical ingredients across membranes. However, commercially available glass-based devices, such as Franz diffusion cells, are expensive and fragile. The emergence of three-dimensional (3D) printing technology enables the creation of diffusion cells with cost-effective polymeric materials and resins, offering exceptional precision and custom geometries. Nonetheless, there are challenges associated with interactions between 3D printing materials and drug molecules. This work aimed to develop inert coatings for 3D-printed diffusion models. Diffusion devices were designed and 3D-printed with a stereolithography (SLA) 3D printer, and different coatings were applied. Then, two model drugs were used to evaluate drug retention by coated devices. Among the tested coatings, one of them showed great potential in preventing drug retention and was selected for subsequent experiments with different drugs and conditions. Finally, voriconazole eyedrops were used to confirm the viability of 3D-printed Franz diffusion cells as a drug release diffusion model. The favourable results obtained with the coating promote the use of 3D printing as a cost-effective manufacturing technology, capable of producing diffusion cells tailored to specific study requirements.

Analysis and Simulation of the Compressive Strength of Bioinspired Lightweight Structures Manufactured by a Stereolithography 3D Printer.

The use of metamaterials is a good alternative when looking for structures that can withstand compression forces without increasing their weight. In this sense, using nature as a reference can be an appropriate option to design this type of material. Therefore, in this work, a comparative study of a selection of eight representative models of a wide variety of existing solutions, both bioinspired and proposed by various researchers, is presented. These models have been manufactured using stereolithography (SLA) printing, which allows complex geometries to be obtained in a simple way that would be more complicated to achieve by other procedures. Additionally, the manufacturing cost of each model has been determined. The compression tests of the different models have made it possible to evaluate the breaking force and its corresponding deformation. Likewise, a finite element analysis of the manufactured models has been carried out to simulate their behavior under compression, achieving results very similar to those obtained in the experimental tests. In this way, it has been concluded that, among the three-dimensional patterns, the structure called "3D auxetic" is the one that supports the greatest breaking force due to the topographic characteristics of its bar structure. Similarly, among the two-dimensional patterns, the structure called "Auxetic 1", with a topography based on curves, is capable of supporting the greatest deformation in the compression direction before breaking. Moreover, the highest resistance-force-to-cost ratio has been obtained with a "3D auxetic" structure.

SLA-3d printed building and characteristics of GelMA/HAP biomaterials with gradient porous structure.

Developing a gradient porous scaffold similar to bone structure is gaining increasing attention in bone tissue engineering. The GelMA/HAP hydrogel has demonstrated potential in bone repair. Although 3D printing can build GelMA/HAP with porous structure, fabricating porous GelMA/HAP with gradient porosity and pore size in one step remains challenging. In this paper, a gradient porous structure with controllable pore size, based on gelatin methacryloyl (GelMA) and hydxroxyapatite (HAP), was engineered and printed using stereolithography. Firstly, the GelMA and HAP were mixed to prepare a hydrogel with a solid content ranging from 10 wt% to 50 wt% for stereolithography. Taking advantage of the sol-gel characteristics of GelMA/HAP hydrogel, GelMA/HAP was fed on the workbench through a combination of extrusion and paving to form a thin layer. During the curing of each layer, the hydrogel exposed to the curing of a single UV beam immediately solidified, forming a highly interconnected porous structure. Additionally, the hydrogel outside the scanning range could be further polymerized to form a relatively dense structure due to the residual laser energy. Finally, without gradient structural design or changing printing parameters, the gradient porous structure of bone-like could be printed in a single-step process. By adjusting the curing parameters of the single UV beam and the concentration and size of ceramic in the hydrogel, the printed pore diameter of the spongy structure could be controlled within the range of 50-260 µm, while the thickness of the compact area could be adjusted within 130-670 µm.

Evaluating and Comparing Flexure Strength of Dental Models Printed Using Fused Deposition Modelling, Digital Light Processing, and Stereolithography Apparatus Printers.

INTRODUCTION: The introduction of three-dimensional (3D) printing in dentistry has mainly focused on applications such as surgical planning, computer-guided templates, and digital impression conversions. Additive manufacturing (AM), also known as 3D printing, involves layering resin material sequentially to construct objects and is gaining recognition for its role in creating custom-made medical appliances. The field of orthodontics has also embraced this technological wave and with the advent of cost-effective printers and biocompatible resins, 3D printing has become increasingly feasible and popular in orthodontic clinics. The limitations of traditional plaster models may have prompted the emergence of 3D-printed models, but it led to enhancing treatment planning and device fabrication, particularly in orthodontics. Notable desktop printing technologies include fused deposition modelling (FDM), digital light processing (DLP), and stereolithography (SLA), each employing distinct methods and materials for fabricating appliances. Evaluating mechanical properties, like flexure strength, is crucial to determine the material's ability to withstand bending forces and thus prove useful in fabricating thermoformable appliances, surgical templates, etc. This study aims to assess the flexure strength of 3D-printed models using FDM, DLP, and SLA technology, providing insights into their suitability as replacements for conventional models and shedding some light on the durability and sustainability of 3D-printed models. MATERIALS AND METHODOLOGY: Cuboids measuring 20 x 5 x 2 mm were cut from models, creating 10 samples per printer group. These samples underwent flexure strength testing using a three-point bending system in a universal testing machine. RESULTS: The FDM group exhibited the highest flexure strength at 69.36 ± 6.03 MPa, while the DLP group showed the lowest flexure strength at 67.47 ± 20.58 MPa. The results can be attributed to the differences in resin materials used for fabrication, with FDM using acrylonitrile butadiene styrene (ABS) polymer and SLA/DLP using polymethyl methacrylate (PMMA), and also to the variation in their printing mechanism. CONCLUSION: The findings affirm the suitability of FDM models for orthodontic applications, suggesting enhanced efficiency and reliability in clinical practices.

Estimating daily semantic segmentation maps of classified ocean eddies using sea level anomaly data from along-track altimetry.

Mesoscale eddies, which are fast-moving rotating water bodies in the ocean with horizontal scales ranging from 10 km to 100 km and above, are considered to be the weather of the oceans. They are of interest to marine biologists, oceanographers, and geodesists for their impact on water mass, heat, and nutrient transport. Typically, gridded sea level anomaly maps processed from multiple radar altimetry missions are used to detect eddies. However, multi-mission sea level anomaly maps obtained by the operational processors have a lower effective spatiotemporal resolution than their grid spacing and temporal resolution, leading to inaccurate eddy detection. In this study, we investigate the use of higher-resolution along-track sea level anomaly data to infer daily two-dimensional segmentation maps of cyclonic, anticyclonic, or non-eddy areas with greater accuracy than using processed sea level anomaly grid map products. To tackle this challenge, we propose a deep neural network that uses spatiotemporal contextual information within the modality of along-track data. This network is capable of producing a two-dimensional segmentation map from data with varying sparsity. We have developed an architecture called Teddy, which uses a Transformer module to encode and process spatiotemporal information, and a sparsity invariant CNN to infer a two-dimensional segmentation map of classified eddies from the ground tracks of varying sparsity on the considered region. Our results show that Teddy creates two-dimensional maps of classified eddies from along-track data with higher accuracy and timeliness when compared to commonly used methods that work with less accurate preprocessed sea level anomaly grid maps. We train and test our method with a carefully curated and independent dataset, which can be made available upon request.

Rotavirus infection inhibits SLA-I expression on the cell surface by degrading ß2 M via ERAD-proteasome pathway.

Group A Rotavirus (RVA) is a major cause of diarrhea in infants and piglets. ß2-microglobulin (ß2 M), encoded by the B2M gene, serves as a crucial subunit of the major histocompatibility complex class I (MHC-I) molecules. ß2 M is indispensable for the transport of MHC-I to the cell membrane. MHC-I, also known as swine leukocyte antigen class I (SLA-I) in pigs, presents viral antigens to the cell surface. In this study, RVA infection down-regulated ß2 M expression in both porcine intestinal epithelial cells-J2 (IPEC-J2) and MA-104 cells. RVA infection did not down-regulate the mRNA level of the B2M gene, indicating that the down-regulation of ß2 M occurred on the protein level. Mechanismly, RVA infection triggered ß2 M aggregation in the endoplasmic reticulum (ER) and enhanced the Lys48 (K48)-linked ubiquitination of ß2 M, leading to the degradation of ß2 M through ERAD-proteasome pathway. Furthermore, we found that RVA infection significantly impeded the level of SLA-I on the surface, and the overexpression of ß2 M could recover its expression. In this study, our study demonstrated that RVA infection degrades ß2 M via ERAD-proteasome pathway, consequently hampering SLA-I expression on the cell surface. This study would enhance the understanding of the mechanism of how RVA infection induces immune escape.

Comparative analysis of swine leukocyte antigen gene diversity in Göttingen Minipigs.

Worldwide, pigs represent economically important farm animals, also representing a preferred preclinical large animal model for biomedical studies. The need for swine leukocyte antigen (SLA) typing is increasing with the expanded use of pigs in translational research, infection studies, and for veterinary vaccine design. Göttingen Minipigs (GMP) attract increasing attention as valuable model for pharmacological studies and transplantation research. This study represents a first-time assessment of the SLA gene diversity in Göttingen Minipigs in combination with a comparative metadata analysis with commercial pig lines. As Göttingen Minipigs could harbor private as well as potential novel SLA allele combinations, future research projects would benefit from the characterization of their SLA background. In 209 Göttingen Minipigs, SLA class I (SLA-1, SLA-2, SLA-3) and class II (DRB1, DQB1, DQA) genes were characterized by PCR-based low-resolution (Lr) haplotyping. Criteria and nomenclature used for SLA haplotyping were proposed by the ISAG/IUIS-VIC SLA Nomenclature Committee. Haplotypes were assigned based on the comparison with already known breed or farm-specific allele group combinations. In total, 14 SLA class I and five SLA class II haplotypes were identified in the studied cohort, to manifest in 26 SLA class I but only seven SLA class II genotypes. The most common SLA class I haplotypes Lr-24.0 (SLA-1*15XX or Blank-SLA-3*04:04-SLA-2*06:01~02) and Lr-GMP-3.0 (SLA-1*16:02-SLA-3*03:04-SLA-2*17:01) occurred at frequencies of 23.44 and 18.66%, respectively. For SLA class II, the most prevalent haplotypes Lr-0.21 (DRB1*01XX-DQB1*05XX-DQA*04XX) and Lr-0.03 (DRB1*03:02-DQB1*03:01-DQA*01XX) occurred at frequencies of 38.28 and 30.38%. The comparative metadata analysis revealed that Göttingen Minipigs only share six SLA class I and two SLA class II haplotypes with commercial pig lines. More importantly, despite the limited number of SLA class I haplotypes, the high genotype diversity being observed necessitates pre-experimental SLA background assessment of Göttingen Minipigs in regenerative medicine, allo-transplantation, and xenograft research.

Wear resistance and flexural properties of low force SLA- and DLP-printed splint materials in different printing orientations: An in vitro study.

OBJECTIVES: To investigate the influence of material and printing orientation on wear resistance and flexural properties of one low force SLA- and two DLP-printed splint materials and to compare these 3D-printed splints to a subtractively manufactured splint material. METHODS: Two DLP-printed (V-Print splint, LuxaPrint Ortho Plus) and one low force SLA-printed (Dental LT Clear) material, where specimens were printed in three printing orientations (0°, 45°, 90°), were investigated. In addition, one milled splint material (Zirlux Splint Transparent) was examined. A total of 160 specimens were produced for both test series. The two-body wear test was performed in a chewing simulator (80'000 cycles at 50 N with 5-55 °C thermocycling). Steatite balls were used as antagonists. The wear pattern was analyzed with a 3D digital microscope in terms of maximum vertical intrusion depth (mm) and total volume loss (mm³). The flexural properties were investigated by three-point bending in accordance with ISO 20795-1: 2013 (denture base polymers). The flexural strength (MPa) and the flexural modulus (MPa) were measured. Two-way ANOVA was performed to investigate the effects of the two independent variables material and printing orientation for the three 3D-printed materials. The comparison of the printing orientations within one material was carried out with one-way ANOVA with post-hoc Tukey tests. RESULTS: Two-way ANOVA revealed that wear and flexural properties are highly dependent on the 3D-printed material (p < 0.001). Across groups, a significant effect was observed for wear depth (p = 0.031) and wear volume (p = 0.044) with regard to printing orientation but this was not found for flexural strength (p = 0.080) and flexural modulus (p = 0.136). One-way ANOVA showed that both DLP-printed groups showed no significant differences within the printing orientations in terms of wear and flexural properties. Dental LT Clear showed that 90° oriented specimens had higher flexural strength than 0° oriented ones (p < 0.001) and 45° oriented specimens also showed higher values than 0° ones (p = 0.038). No significant differences were observed within the printing orientations for flexural modulus and wear behaviour within this group. T-tests showed that the milled splints exhibited statistically higher wear resistance and flexural properties compared to all three 3D-printed splint materials (p < 0.001) and that highly significant differences were found between the 3D-printed splint materials for both test series. CONCLUSION: Within the limitations of this in vitro study, it can be stated that wear behaviour and flexural properties are highly dependent on the 3D-printed material itself. Currently, milled splints exhibit higher wear resistance and flexural properties compared to 3D-printed splint materials. The printing orientation has a minor influence on the properties investigated. Nevertheless, two-way ANOVA also showed a significant influence of printing orientation in the wear test across groups and one-way ANOVA detected significant effects for SLA material in terms of flexural strength, with printing in 90° showing the highest flexural strength. Therefore, anisotropy was found in SLA material, but it can be limited with the employed printing parameters. Both DLP-printed materials showed no significant difference within the printing orientation.

Characterization of SLA RNA promoter from dengue virus and its interaction with the viral non-structural NS5 protein.

The Dengue virus (DENV) is the most significant arthropod-borne viral pathogen in humans with 400 million infections annually. DENV comprises four distinct serotypes (DENV-1 to -4) which complicates vaccine development. Any of the four serotypes can cause clinical illness but with distinctive infection dynamics. Variations in sequences identified within the four genomes induce structural differences in crucial RNA motifs that were suggested to be correlated to the degree of pathogenicity among DENV-1 to -4. In particular, the RNA Stem-loop A (SLA) at the 5'-end of the genome, acts as a key regulator of the viral replication cycle by interacting with the viral NS5 polymerase to initiate the minus-strand viral RNA synthesis and later to methylate and cap the synthesized RNA. The molecular details of this interaction remain not fully described. Here, we report the solution secondary structures of SLA from DENV-1 to -4. Our results highlight that the four SLA exhibit structural and dynamic differences. Secondly, to determine whether SLA RNA contains serotype-specific determinants for the recognition by the viral NS5 protein, we investigated interactions between SLA from DENV -1 to -4 and DENV2 NS5 using combined biophysical approaches. Our results show that NS5 from DENV2 is able to bind SLA from other serotypes, but that other viral or host factors may be necessary to stabilize the complex and promote the catalytically active state of the NS5. By contrast, we show that a serotype-specific binding is driven by specific interactions involving conformational changes within the SLA RNA.

Evaluation of the effect of diode laser application on the hydrophilicity, surface topography, and chemical composition of titanium dental implant surface.

PURPOSE: Attempts have been made to decontaminate the implant surface by using diode lasers. However, the parameters that provide efficient decontamination without altering the topography or surface characteristics of titanium implants are still unclear. The aim of the present study was to evaluate the effect of altering the power of diode laser (940 nm) application on the hydrophilicity, surface topography, and chemical composition of sandblasted, large grit, acid-etched (SLA) treated titanium alloy implant surface. MATERIALS AND METHODS: Thirty-six SLA-treated titanium discs (Dentis Co., Ltd.) were used in this study. The hydrophilicity of all discs was measured by using a contact angle goniometer (190 CA; Rame-hart Co, Ltd). Discs were randomly divided into four groups (n = 9 each) based on the power of the diode laser used. Group I (control, no lasing group), group II: treated with 1 W power, group III: 2 W power, and group IV: 3 W power. The chemical composition of the SLA discs was evaluated by using energy dispersive x-ray spectroscopy (EDX) before laser application. Hydrophilicity was reevaluated after the application of laser irradiation. The surface topography of all discs was examined. Changes in the chemical composition of the titanium discs were investigated following the lasing procedure. Morphometric analysis of the surface area (µm2 ) of the indentations created following laser application was also evaluated. Data were collected and the Shapiro-Wilk test of normality was used. Comparisons between the four study groups were done by using the Kruskal-Wallis test, while that to evaluate the morphometric analysis of the surface area was done by using One-way ANOVA (P < 0.05). RESULTS: The average contact angle of the drop of distilled water to the SLA discs significantly decreased after laser treatment (P < 0.05). The largest contact angle was measured in the control group, followed by the 1 W group, and the 2 W group. The smallest angle was measured in the 3 W group. Considerable surface alterations such as melting and flattening were observed on examination of the surface topography of the 3 W group followed by the 2 W group. The least changes were observed in association with the 1 W group in comparison to the control group. The EDX analysis showed the appearance of peaks of the oxygen and carbon elements after the lasing procedure with the highest percentage in the 3 W group. The average of the surface area of the created indentations significantly increased with increasing the power of the diode laser used (P < 0.05). CONCLUSIONS: The application of diode laser (940 nm) with 2 W and 3 W powers significantly altered the hydrophilicity, the surface topography, and the chemical composition of titanium discs. Diode laser (940 nm) with 1 W power can be safely used on SLA titanium implant surfaces with no damaging effect on the surface topography or hydrophilicity.

Combining multiple investigative approaches to unravel functional responses to global change in the understorey of temperate forests.

Plant communities are being exposed to changing environmental conditions all around the globe, leading to alterations in plant diversity, community composition, and ecosystem functioning. For herbaceous understorey communities in temperate forests, responses to global change are postulated to be complex, due to the presence of a tree layer that modulates understorey responses to external pressures such as climate change and changes in atmospheric nitrogen deposition rates. Multiple investigative approaches have been put forward as tools to detect, quantify and predict understorey responses to these global-change drivers, including, among others, distributed resurvey studies and manipulative experiments. These investigative approaches are generally designed and reported upon in isolation, while integration across investigative approaches is rarely considered. In this study, we integrate three investigative approaches (two complementary resurvey approaches and one experimental approach) to investigate how climate warming and changes in nitrogen deposition affect the functional composition of the understorey and how functional responses in the understorey are modulated by canopy disturbance, that is, changes in overstorey canopy openness over time. Our resurvey data reveal that most changes in understorey functional characteristics represent responses to changes in canopy openness with shifts in macroclimate temperature and aerial nitrogen deposition playing secondary roles. Contrary to expectations, we found little evidence that these drivers interact. In addition, experimental findings deviated from the observational findings, suggesting that the forces driving understorey change at the regional scale differ from those driving change at the forest floor (i.e., the experimental treatments). Our study demonstrates that different approaches need to be integrated to acquire a full picture of how understorey communities respond to global change.