Enhancing Honey Bee Health: Evaluating Pollen Substitute Diets in Field and Cage Experiments.

Honey bees (Apis mellifera L.) play vital roles as agricultural pollinators and honey producers. However, global colony losses are increasing due to multiple stressors, including malnutrition. Our study evaluated the effects of four pollen substitute diets (Diet 1, Diet 2, Diet 3, and Control) through field and cage experiments, analyzing 11 parameters and 21 amino acids. Notably, Diet 1 demonstrated significantly superior performance in the field experiment, including the number of honey bees, brood area, consumption, preference, colony weight, and honey production. In the cage experiment, Diet 1 also showed superior performance in dried head and thorax weight and vitellogenin (vg) gene expression levels. Canonical discriminant and principle component analyses highlighted Diet 1's distinctiveness, with histidine, diet digestibility, consumption, vg gene expression levels, and isoleucine identified as key factors. Arginine showed significant correlations with a wide range of parameters, including the number of honey bees, brood area, and consumption, with Diet 1 exhibiting higher levels. Diet 1, containing apple juice, soytide, and Chlorella as additive components, outperformed the other diets, suggesting an enhanced formulation for pollen substitute diets. These findings hold promise for the development of more effective diets, potentially contributing to honey bee health.

The Effects of Artificial Diets on the Expression of Molecular Marker Genes Related to Honey Bee Health.

Honey bees are commonly used to study metabolic processes, yet the molecular mechanisms underlying nutrient transformation, particularly proteins and their effects on development, health, and diseases, still evoke varying opinions among researchers. To address this gap, we investigated the digestibility and transformation of water-soluble proteins from four artificial diets in long-lived honey bee populations (Apis mellifera ligustica), alongside their impact on metabolism and DWV relative expression ratio, using transcriptomic and protein quantification methods. Diet 2, characterized by its high protein content and digestibility, was selected for further analysis from the other studied diets. Subsequently, machine learning was employed to identify six diet-related molecular markers: SOD1, Trxr1, defensin2, JHAMT, TOR1, and vg. The expression levels of these markers were found to resemble those of honey bees who were fed with Diet 2 and bee bread, renowned as the best natural food. Notably, honey bees exhibiting chalkbrood symptoms (Control-N) responded differently to the diet, underscoring the unique nutritional effects on health-deficient bees. Additionally, we proposed a molecular model to elucidate the transition of long-lived honey bees from diapause to development, induced by nutrition. These findings carry implications for nutritional research and beekeeping, underscoring the vital role of honey bees in agriculture.

A Finite Element Analysis Study of Edentulous Model with Complete Denture to Simulate Masticatory Movement.

The purposes of this study are to establish and validate a finite element (FE) model using finite element analysis methods and to identify optimal loading conditions to simulate masticatory movement. A three-dimensional FE model of the maxillary and mandibular cortical bone, cancellous bone, and gingiva was constructed based on edentulous cone-beam-computed tomography data. Dental computer-aided design software was used to design the denture base and artificial teeth to produce a complete denture. Mesh convergence was performed to derive the optimal mesh size, and validation was conducted through comparison with mechanical test results. The mandible was rotated step-by-step to induce movements similar to actual mastication. Results showed that there was less than a 6% difference between the mechanical test and the alveolar bone-complete denture. It opened 10° as set in the first stage, confirming that the mouth closed 7° in the second stage. Occlusal contact occurred between the upper and lower artificial teeth as the mouth closed the remaining angle of 3° in the third stage while activating the masseter muscle. These results indicate that the FE model and masticatory loading conditions developed in this study can be applied to analyze biomechanical effects according to the wearing of dentures with various design elements applied.

Geographical Characteristics of Culex tritaeniorhynchus and Culex orientalis Microbiomes in Korea.

Mosquitoes, the primary vectors of arboviruses, harbor a diverse microbiome that plays a crucial role in their development, immunity, and vector competence. The composition of the mosquito microbiome is heavily influenced by the environment and habitats. Therefore, identifying the relationship between the habitat and the mosquito's microbial community can improve the overall understanding of mosquito biology. However, The microbiome profiles of Culex tritaeniorhynchus and Culex orientalis, known as transmission vectors of the Japanese encephalitis virus, are poorly understood. Using 16S rRNA Illumina sequencing, we hereby investigated the microbial profiles in these two mosquito species collected in several areas in the Republic of Korea. Thirty-six prevalent bacterial families were identified from these mosquito species. The microbial composition variations were primarily influenced by the mosquito collecting sites. Moreover, species biomarkers were identified by utilizing the regional specificity of the mosquito microbiome. Based on the microbiome profiles representing high similarity, Culex orientalis may share an ecological niche with Culex tritaeniorhynchus.

Gut Microbiota of Apis mellifera at Selected Ontogenetic Stages and Their Immunogenic Potential during Summer.

Honeybees (Apis mellifera) are pollinating agents of economic importance. The role of the gut microbiome in honeybee health has become increasingly evident due to its relationship with immune function, growth, and development. Although their dynamics at various developmental stages have been documented, their dynamics during the era of colony collapse disorder and immunogenic potential, which are connected to the antagonistic immune response against pathogens, need to be elucidated. Using 16S rRNA gene Illumina sequencing, the results indicated changes in the gut microbiota with the developmental stage. The bacterial diversity of fifth stage larva was significantly different among the other age groups, in which Fructobacillus, Escherichia-Shigella, Bombella, and Tyzzerella were unique bacteria. In addition, the diversity of the worker bee microbiome was distinct from that of the younger microbiome. Lactobacillus and Gilliamella remained conserved throughout the developmental stages, while Bifidobacterium colonized only worker bees. Using an in silico approach, the production potential of lipopolysaccharide-endotoxin was predicted. Forager bees tend to have a higher abundance rate of Gram-negative bacteria. Our results revealed the evolutionary importance of some microbiome from the larval stage to the adult stage, providing insight into the potential dynamics of disease response and susceptibility. This finding provides a theoretical foundation for furthering the understanding of the function of the gut microbiota at various developmental stages related to probiotic development and immunogenic potential.

Comparative Study of the Effect of Pollen Substitute Diets on Honey Bees during Early Spring.

The nutritional quality of a colony significantly affects its health and strength, particularly because it is required for population growth in the early spring. We investigated the impact of various artificial pollen substitute diets on colony performance in the Republic of Korea during early spring, a critical period for colony health and growth. The colonies were provided with different diets, including the commercial product Megabee (positive control), our developed diet Test A, and four upgraded versions (Diet 1, Diet 2, Diet 3, and Diet 4) of Test A. The negative control group received no supplementary feed. Over 63 days, we observed 24 experimental colonies and assessed various parameters at the colony and individual levels. The results revealed that Diet 2 had the highest consumption and had the most positive impact on population growth, the capped brood area, colony weight, honey bees' weight, and vitellogenin levels. These findings suggested that Diet 2 is most attractive to honey bees and thus holds great promise for improving colony maintenance and development during the crucial early spring period.

Modifying Kohlrausch's Law to Describe Nonaqueous Electrolytes for Lithium-Ion Batteries.

To develop next-generation lithium-ion batteries with enhanced stability and safety, it is crucial to understand the physicochemical principles of nonaqueous electrolytes. Kohlrausch's law describes a linear decrease in the molar conductivity (Λ) with respect to the square root of the molarity of strong electrolytes at lower concentrations. This empirical law explains the impeded ionic mobility at higher concentrations due to ionic interactions, i.e., relaxation and asymmetric effects. However, this law does not hold at higher concentrations due to the ionic association that alleviates the ionic interactions and retards the decrease in the Λ. Especially, the anomalously stagnant decrease in the Λ near the solubility limit has not been clearly explained, calling for the consideration of other concentration-dependent factors such as the mean activity coefficient (γ±), viscosity (η), and dielectric constant (ε). Herein, we develop a systematic method to modify Kohlrausch's law. First, we install the ionic association constant, and the theoretical estimation is compared with the experimental results to induce the correction function that is related with the previously neglected concentration-dependent factors. Thus, the induced correction function was close to the rectified linear unit (ReLU) function, which has been widely used in the field of artificial intelligence. The modified Kohlrausch's law with the ReLU-type correction function provides a highly precise and reliable data fitting, and the fitted parameters showed clear concentration dependency and straightforward interpretability. As a result, this method effectively generalized Kohlrausch's law for nonaqueous electrolytes at higher concentrations up to the solubility limit of 3.0-3.5 M. Moreover, the modified Kohlrausch's law inspired us to discover the physical origins of the anomalously stagnant Λ profiles near the solubility limit; and the most relevant physical origin of the anomaly was the concentration dependency of the γ± and η, which grow exponentially above a critical concentration.

Apigenin's Therapeutic Potential Against Viral Infection.

Several antiviral drugs are clinically approved to treat influenza that is a highly prevalent acute respiratory disease. However, emerging drug-resistant virus strains undermine treatment efficacy, highlighting the exigency for novel antiviral drugs to counter these drug-resistant strains. Plants and their derivates have been historically utilized as medicinal remedies, and extensive studies have evidenced the antiviral potential of phytochemicals. Notably, apigenin is a predominant flavonoid with minimal toxicity and substantial therapeutic effects in various disease models. Despite its many anti-inflammatory, anti-oxidant, anti-cancer, anti-bacterial, and other beneficial bioactivities, existing reviews have yet to focus on apigenin's antiviral effects. Therefore, this review elucidates apigenin's therapeutic and antiviral properties in vitro and in vivo, discussing its mode of action and future prospects. Apigenin's remarkable inhibition by modulating multiple mechanisms against viruses has promising potential for novel plant-derived antiviral drugs and further clinical study developments.

Strategic design of gold nanocatalysts for effective photocatalytic organic transformation.

We demonstrate the design strategy of free-standing Au nanocatalysts by correlating their physicochemical characteristics with photocatalytic performance. By tailoring the particle size and surface characteristics, we found that small Au nanocatalysts called Au nanoclusters with discrete energy levels are more effective than large metallic Au nanoparticles, while the microenvironments (e.g., charge status and hydrophilicity/hydrophobicity) around the surface of Au-nanoclusters are crucial in determining the performance. With the optimized Au nanocatalyst, under visible light, decarboxylative radical addition reactions for C-C bond formation (i.e., Giese reaction) were first achieved with high yields and further utilized for the preparation of one of the bioactive γ-aminobutyric acid derivatives, pregabalin (Lyrica®), demonstrating its potential in pharmaceutical applications.

Complementary Analysis for Undetectable Microplastics from Contact Lenses to Aquatic Environments via Fourier Transform Infrared Spectroscopy.

Although microplastics (MPs) are intrinsically toxic and function as vectors for organic micropollutants, their discharge from wastewater treatment plant effluents and human activity remains unknown owing to the limitations of detection and treatment technologies. It is imperative to quantify MPs from human activities involving the consumption of various plastic products. This study warns that contact lenses can generate MPs and nanoplastics (NPs) after being discharged into aquatic environments. Identification via micro-Fourier transform infrared spectroscopy revealed that the fragmented particles (from a few tens to a few hundred micrometres) could not be detected as poly(2-hydroxyl methacrylate), the component of contact lenses, owing to changes in its chemical properties. After the degradation process, the median size of the contact lens particles decreased from 313 to 85 µm. Approximately 300,600 g of contact lens waste is discharged into sewage systems daily in the United States of America (USA), where 45 million people wear contact lenses and throw away one-fifth of them every day. Contact lens waste (1 g) has the potential to release 5653.3-17,773.3 particles of MPs. This implies that the currently reported MP amounts in the environmental matrix exclude significant amounts of MPs and NPs from discharged contact lenses. The identification method should be examined, and a registration of the disposal process should be established.

Uniform Gold Nanostructure Formation via Weakly Adsorbed Gold Films and Thermal Annealing for Reliable Localized Surface Plasmon Resonance-Based Detection of DNase-I.

Deoxyribonuclease-I (DNase-I), a representative endonuclease, is an important biomarker for the diagnosis of infectious diseases and cancer progression. However, enzymatic activity decreases rapidly ex vivo, which highlights the need for precise on-site detection of DNase-I. Here, a localized surface plasmon resonance (LSPR) biosensor that enables the simple and rapid detection of DNase-I is reported. Moreover, a novel technique named electrochemical deposition and mild thermal annealing (EDMIT) is applied to overcome signal variations. By taking advantage of the low adhesion of gold clusters on indium tin oxide substrates, both the uniformity and sphericity of gold nanoparticles are increased under mild thermal annealing conditions via coalescence and Ostwald ripening. This ultimately results in an approximately 15-fold decrease in LSPR signal variations. The linear range of the fabricated sensor is 20-1000 ng mL-1 with a limit of detection (LOD) of 127.25 pg mL-1 , as demonstrated by spectral absorbance analyses. The fabricated LSPR sensor stably measured DNase-I concentrations from samples collected from both an inflammatory bowel disease (IBD) mouse model, as well as human patients with severe COVID-19 symptoms. Therefore, the proposed LSPR sensor fabricated via the EDMIT method can be used for early diagnosis of other infectious diseases.

Hybrid Nanogenerators for Ocean Energy Harvesting: Mechanisms, Designs, and Applications.

The ocean holds vast potential as a renewable energy source, but harnessing its power has been challenging due to low-frequency and high-amplitude stimulation. However, hybrid nanogenerators (HNGs) offer a promising solution to convert ocean energy into usable power efficiently. With their high sensitivity and flexible design, HNGs are ideal for low-frequency environments and remote ocean regions. Combining triboelectric nanogenerators (TENGs) with piezoelectric nanogenerators (PENGs) and electromagnetic nanogenerators (EMGs) creates a unique hybrid system that maximizes energy harvesting. Ultimately, hybrid energy-harvesting systems offer a sustainable and reliable solution for growing energy needs. This study provides an in-depth review of the latest research on ocean energy harvesting by hybrid systems, focusing on self-powered applications. The article also discusses primary hybrid designs for devices, powering self-powered units such as wireless communication systems, climate monitoring systems, and buoys as applications. The potential of HNGs is enormous, and with rapid advancements in research and fabrication, these systems are poised to revolutionize ocean energy harvesting. It outlines the pros and cons of HNGs and highlights the major challenges that must be overcome. Finally, future outlooks for hybrid energy harvesters are also discussed.

Thymosin Beta 4 Inhibits LPS and ATP-Induced Hepatic Stellate Cells via the Regulation of Multiple Signaling Pathways.

Risk signals are characteristic of many common inflammatory diseases and can function to activate nucleotide-binding oligomerization (NLR) family pyrin domain-containing 3 (NLRP3), the innate immune signal receptor in cytoplasm. The NLRP3 inflammasome plays an important role in the development of liver fibrosis. Activated NLRP3 nucleates the assembly of inflammasomes, leading to the secretion of interleukin (IL)-1ß and IL-18, the activation of caspase-1, and the initiation of the inflammatory process. Therefore, it is essential to inhibit the activation of the NLRP3 inflammasome, which plays a vital role in the immune response and in initiating inflammation. RAW 264.7 and LX-2 cells were primed with lipopolysaccharide (LPS) for 4 h and subsequently stimulated for 30 min with 5 mM of adenosine 5'-triphosphate (ATP) to activate the NLRP3 inflammasome. Thymosin beta 4 (Tß4) was supplemented to RAW264.7 and LX-2 cells 30 min before ATP was added. As a result, we investigated the effects of Tß4 on the NLRP3 inflammasome. Tß4 prevented LPS-induced NLRP3 priming by inhibiting NF-kB and JNK/p38 MAPK expression and the LPS and ATP-induced production of reactive oxygen species. Moreover, Tß4 induced autophagy by controlling autophagy markers (LC3A/B and p62) through the inhibition of the PI3K/AKT/mTOR pathway. LPS combined with ATP significantly increased thee protein expression of inflammatory mediators and NLRP3 inflammasome markers. These events were remarkably suppressed by Tß4. In conclusion, Tß4 attenuated NLRP3 inflammasomes by inhibiting NLRP3 inflammasome-related proteins (NLRP3, ASC, IL-1ß, and caspase-1). Our results indicate that Tß4 attenuated the NLRP3 inflammasome through multiple signaling pathway regulations in macrophage and hepatic stellate cells. Therefore, based on the above findings, it is hypothesized that Tß4 could be a potential inflammatory therapeutic agent targeting the NLRP3 inflammasome in hepatic fibrosis regulation.

Monitoring Immune Modulation in Season Population: Identifying Effects and Markers Related to Apis mellifera ligustica Honey Bee Health.

Honey bees play a significant role in ecology, producing biologically active substances used to promote human health. However, unlike humans, the molecular markers indicating honey bee health remain unknown. Unfortunately, numerous reports of honey bee collapse have been documented. To identify health markers, we analyzed ten defense system genes in Apis mellifera ligustica honey bees from winter (Owb) and spring (Fb for foragers and Nb for newly emerged) populations sampled in February and late April 2023, respectively. We focused on colonies free from SBV and DWV viruses. Molecular profiling revealed five molecular markers of honey bee health. Of these, two seasonal molecular markers-domeless and spz genes-were significantly downregulated in Owb compared to Nb and Fb honey bees. One task-related marker gene, apid-1, was identified as being downregulated in Owb and Nb compared to Fb honey bees. Two recommended general health markers, SOD and defensin-2, were upregulated in honey bees. These markers require further testing across various honey bee subspecies in different climatic regions. They can diagnose bee health without colony intervention, especially during low-temperature months like winter. Beekeepers can use this information to make timely adjustments to nutrients or heating to prevent seasonal losses.

Biomechanical Efficacy and Effectiveness of Orthodontic Treatment with Transparent Aligners in Mild Crowding Dentition-A Finite Element Analysis.

Orthodontic treatment increasingly involves transparent aligners; however, biomechanical analysis of their treatment effects under clinical conditions is lacking. We compared the biomechanical efficacy and effectiveness of orthodontic treatment with transparent aligners and of fixed appliances in simulated clinical orthodontic treatment conditions using orthodontic finite element (FE) models. In the FE analysis, we used Model Activation/De-Activation analysis to validate our method. Fixed appliances and 0.75-mm and 0.5-mm thick transparent aligners were applied to a tooth-alveolar bone FE model with lingually-inclined and axially-rotated central incisors. Compared to the fixed appliance, the 0.75-mm and 0.5-mm transparent aligners induced 5%, 38%, and 28% and 21%, 62%, and 34% less movement of the central incisors and principal stress of the periodontal ligament and of the alveolar bone, respectively, for lingual inclination correction. For axial-rotation correction, these aligners induced 22%, 37%, and 40% and 28%, 67%, and 48% less tooth movement and principal stress of the periodontal ligament and of the alveolar bone, respectively. In conclusion, transparent aligners induced less tooth movement, it is sufficient for orthodontic treatment, but 0.5-mm aligners should be used for only mild corrections. Additionally, the Model Activation/De-Activation analysis method is suitable for FE analysis of orthodontic treatment reflecting clinical treatment conditions.

Single metal-organic framework-embedded nanopit arrays: A new way to control neural stem cell differentiation.

Stable and continuous supply of essential biomolecules is critical to mimic in vivo microenvironments wherein spontaneous generation of various cell types occurs. Here, we report a new platform that enables highly efficient neuronal cell generation of neural stem cells using single metal-organic framework (MOF) nanoparticle-embedded nanopit arrays (SMENA). By optimizing the physical parameters of homogeneous periodic nanopatterns, each nanopit can confine single nMOFs (UiO-67) that are specifically designed for long-term storage and release of retinoic acid (RA). The SMENA platform successfully inhibited physical interaction with cells, which contributed to remarkable stability of the nMOF (RA⊂UiO-67) structure without inducing nanoparticle-mediated toxicity issues. Owing to the continuous and long-term supply of RA, the neural stem cells showed enhanced mRNA expressions of various neurogenesis-related activities. The developed SMENA platform can be applied to other stem cell sources and differentiation lineages and is therefore useful for various stem cell-based regenerative therapies.

Saponins of Korean Red Ginseng May Protect Human Skin from Adipokine-Associated Inflammation and Pigmentation Resulting from Particulate Matter Exposure.

BACKGROUND: Exposure to airborne particulate matter (PM) is an ever-increasing concern worldwide. Strategies to counter the detrimental effects that follow cutaneous exposure to PM, such as induction of pigmentation, inflammation, and alterations in adipokine profile, need to be investigated further. Korean red ginseng (KRG) extracts and individual ingredients have been demonstrated to play an effective role in suppression of ROS, inflammation, and resultant skin aging. In addition, recent investigations revealed that Rg3 and Rf saponins work as antimelanogenic agents. In this study, we investigated whether saponins of KRG can protect against or reverse the PM-induced detrimental effects. METHODS: The biological effects of PM and saponins were evaluated both in vitro and ex vivo. Cell viability and intracellular ROS levels were determined in normal human epidermal melanocytes (NHMs), human epidermal keratinocytes (NHKs), and their cocultures. Experiments to demonstrate the protective properties of saponins against consequences of exposure to PM were performed. Melanin assay, quantitative real-time PCR, and Western blotting were carried out to determine the effects on melanogenesis and the implicated molecular signaling pathways. RESULTS: Exposure to PM resulted in decreased keratinocyte viability, which was coupled with augmented oxidative stress. These changes were attenuated by treatment with saponins. PM exposure resulted in increased expression of leptin, which was reduced by saponins. Moreover, PM exposure led to increased melanin production in a coculture model, which was mitigated by treatment with saponins. Treatment with saponins resulted in a decrease in matrix metalloproteinase (MMP) levels after exposure to PM. CONCLUSION: Saponins of KRG can protect the skin from the harmful effects of PM exposure by reducing levels of ROS, leptin, inflammatory cytokines, and melanin.

Downsizing of Block Polymer-Templated Nanopores to One Nanometer via Hyper-Cross-Linking of High χ-Low N Precursors.

Synthesizing nanoporous polymer from the block polymer template by selective removal of the sacrificial domain offers straightforward pore size control as a function of the degree of polymerization (N). Downscaling pore size into the microporous regime (<2 nm) has been thermodynamically challenging, because the low N drives the system to disorder and the small-sized pore is prone to collapse. Herein, we report that maximizing cross-linking density of a block polymer precursor with an increased interaction parameter (χ) can help successfully stabilize the structure bearing pore sizes of 1.1 nm. We adopt polymerization-induced microphase separation (PIMS) combined with hyper-cross-linking as a strategy for the preparation of the bicontinuous block polymer precursors with a densely cross-linked framework by copolymerization of vinylbenzyl chloride with divinylbenzene and also Friedel-Crafts alkylation. Incorporating 4-vinylbiphenyl as a higher-χ comonomer to the sacrificial polylactide (PLA) block and optimizing the segregation strength versus cross-linking density allow for further downscaling. Control of pore size by N of PLA is demonstrated in the range of 9.9-1.1 nm. Accessible surface area to fluorescein-tagged dextrans is regulated by the relative size of the pore to the guest, and pore size is controlled. These findings will be useful for designing microporous polymers with tailored pore size for advanced catalytic and separation applications.

Concerns and breakthroughs of combining ionic liquids with microwave irradiation for the synthesis of Ru nanoparticles via decarbonylation.

HYPOTHESIS: Combination of microwave irradiation (MWI) and ionic liquids (IL) is widely used for the synthesis of nanoparticles (NP) via decarbonylation of zero-valent metal carbonyl precursors. However, we carefully raise a question as to whether this combination is always beneficial. Upon MWI, highly-absorbing materials such as ILs would be subject to local intense heating, likely resulting in the occurrence of localized chemical decomposition. The decomposition is expected to influence the growth mechanism of NPs due to changes in the electrostatic and steric effects. If the assumption is valid, it should be possible to decompose IL and destabilize the NPs by modifying the amplitude of the incident microwaves. In other words, it should also be possible to control the particle aggregation by circumventing the decomposition of the IL. EXPERIMENTS: A series of comparative studies were conducted using a model system (i.e. [BMIm][BF4] and Ru3(CO)12). Variables were systematically controlled. After MWI, the decrease in colloidal stability of NPs was identified. FINDINGS: In the formation of Ru NPs via decarbonylation, the association between incident microwave intensity, chemical decomposition of IL, and initiation of particle aggregation has been demonstrated. Conditions that can accelerate or alleviate the decomposition and the aggregation are also corroborated.

Comparative Analysis of Stress in the Periodontal Ligament and Center of Rotation in the Tooth after Orthodontic Treatment Depending on Clear Aligner Thickness-Finite Element Analysis Study.

Lately, in orthodontic treatments, the use of transparent aligners for the correction of malocclusions has become prominent owing to their intrinsic advantages such as esthetics, comfort, and minimal maintenance. Attempts at improving upon this technology by varying various parameters to investigate the effects on treatments have been carried out by several researchers. Here, we aimed to investigate the biomechanical and clinical effects of aligner thickness on stress distributions in the periodontal ligament and changes in the tooth's center of rotation. Dental finite element models comprising the cortical and cancellous bones, gingiva, teeth, and nonlinear viscoelastic periodontal ligaments were constructed, validated, and used together with aligner finite element models of different aligner thicknesses to achieve the goal of this study. The finite element analyses were conducted to simulate the actual orthodontic aligner treatment process for the correction of malocclusions by generating pre-stresses in the aligner and allowing the aligner stresses to relax to induce tooth movement. The results of the analyses showed that orthodontic treatment in lingual inclination and axial rotation with a 0.75 mm-thick aligner resulted in 6% and 0.03% higher principal stresses in the periodontal ligament than the same treatment using a 0.05 mm-thick aligner, respectively. Again, for both aligner thicknesses, the tooth's center of rotation moved lingually and towards the root direction in lingual inclination, and diagonally from the long axis of the tooth in axial rotation. Taken together, orthodontic treatment for simple malocclusions using transparent aligners of different thicknesses will produce a similar effect on the principal stresses in the periodontal ligament and similar changes in the tooth's center of rotation, as well as sufficient tooth movement. These findings provide orthodontists and researchers clinical and biomechanical evidence about the effect of transparent aligner thickness selection and its effect on orthodontic treatment.