Penetration Technique Research Articles

Comparative Evaluation of Microleakage and Compressive Strength of Different Restorative Materials – An in vitro Study

ABSTRACT Background: For dental restorations to be successful in clinical practice, they must possess excellent mechanical properties, such as high compressive strength and microleakage resistance. Materials and Methods: A total of 80 Class V cavities were prepared from extracted human teeth, divided into four groups of 20 (Groups A, B, C, and D). One of the following restorative materials Neo–Spectra ST, Activa Bioactive Material, SDR Bulkfill Flowable Composite, or Zirconomer was used to restore each group. Standardized testing procedures were used to evaluate compressive strength, and dye penetration techniques were used to measure microleakage. ANOVA and Tukey’s post hoc test, were two of the statistical procedures used to compare the performance of the various materials. Results: Neo Spectra ST had the lowest average microleakage score of 0.5 mm, which was significantly lower compared to Activa Bioactive Material at 1.2 mm, SDR Bulkfill Flowable Composite at 0.8 mm, and Zirconomer at 1.5 mm. In terms of compressive strength, Neo Spectra ST showed the highest average value at 120 MPa, with SDR Bulkfill Flowable Composite following at 100 MPa, Activa Bioactive Material at 80 MPa, and Zirconomer at 60 MPa. Statistical analysis showed significant variations in both microleakage and compressive strength between the materials (P < 0.05), highlighting Neo Spectra ST’s excellent performance. Conclusion: Amongst all materials, Neo Spectra ST demonstrated the greatest compressive strength and microleakage resistance compared to Zirconomer, SDR Bulkfill Flowable Composite, and Activa Bioactive Material.

The Effect of Different Obturation Techniques on the Sealing Ability of Root Canal Filling Materials

ABSTRACT Background: The performance of root canal filling materials in sealing is crucial for the effectiveness of endodontic procedures as it prevents the escape of microorganisms and guarantees the durability of the treatment. Materials and Methods: The present in vitro investigation included the preparation of 90 human single-rooted teeth using a standardized process. These teeth were then randomly separated into three groups (n = 30) according to the obturation technique: Group A (Lateral Compaction), Group B (Thermafil), and Group C (Continuous Wave of Condensation). Furthermore, each group was separated into two subgroups based on the specific kind of root canal filling material employed: Subgroup 1 (Gutta-Percha) and Subgroup 2 (Resilon). The sealing capacity was evaluated using a dye penetration technique, with measurements conducted at three specific time intervals: 24 hours, 1 week, and 4 weeks after the obturation process. Statistical analysis of the data was conducted using analysis of variance and post hoc tests to identify significant differences across groups. Results: The findings showed that the Continuous Wave of Condensation method (Group C) had the lowest dye penetration, with an average depth of penetration of 1.2 mm. The Thermafil technique (Group B) followed closely with a penetration depth of 1.8 mm, while the Lateral Compaction technique (Group A) achieved a penetration depth of 2.5 mm. In terms of sealing ability, Gutta-Percha demonstrated superior performance compared to Resilon, achieving average penetration depths of 1.5 mm and 2.0 mm, respectively. Statistical analysis showed statistically significant differences between the groups (P < 0.05), with the Continuous Wave of Condensation approach utilizing Gutta-Percha showing the highest level of sealing effectiveness. Conclusion: In conclusion, the Continuous Wave of Condensation approach showed a substantial improvement in the sealing efficacy of root canal fillings when compared to the Lateral Compaction and Thermafil procedures.

Antiaging synergistic effect in noninvasive transdermal delivery of peptide loaded liposomes by low energy/frequency radiofrequency

Low energy/frequency radiofrequency (LRF) combined with the transdermal delivery of liposome (L) encapsulated antiaging peptides technology is a remarkable, newly developed physical noninvasive transdermal penetration technique; it is considered a highly efficient, comprehensive and safe technology. In this study, our objective was to evaluate the physical and chemical mechanisms underlying the efficacy of this innovative technique involving a combination of LRF and L, termed LLRF, that exerts a synergistic anti-aging effect on human skin, via an animal experiment. Physical and chemical analyses indicated that a relatively stable liposome with a uniform nano-size, which was formed, possessed good transdermal permeability that was 2.74 folds higher than that of the free peptide (F). LLRF exhibited a higher transdermal permeation performance that was of 3.65 folds higher than that of the free one, which was substantiated via confocal laser scanning fluorescence microscopy. The mouse UVB photoaging model trial confirmed that the LLRF technology exerted a significant synergistic effect compared to liposome technology, or free peptide, by downregulating inflammatory factors (IL-6, TNF-α), inhibiting the mRNA and protein expression of matrix metalloproteinases (MMP1, MMP3), promoting the mRNA and protein expression of related collagens (Procollagen, Col1α1 and Col3α1), and repairing the stratum corneum barrier function, as evidenced by trans-epidermal water loss (TEWL), skin cuticle hydration (SCH), and decreased expression of β-gal, an aging marker. These findings indicated that photoaging skin can be effectively and comprehensively rejuvenated, and that even photodamage can be reversed, thereby restoring the original physiological characteristics of healthy skin. Clinical tests have confirmed that although liposome technology is an effective antiaging method which helps exert tightening and anti-wrinkle effects on human skin, LLRF is an even more effective anti-aging technique. This study reveals a highly effective technique involving a combination physical and chemical therapy that may be utilized for antiaging purposes as well as repairing lightly damaged skin, and can be made readily available in the future.

Comparison of different cementing techniques for cement penetration under tibial component in total knee arthroplasty: a retrospective observational study

PurposeThis study aimed to investigate the differences in cement penetration between cementing techniques in total knee arthroplasty (TKA).Materials and methodsWe retrospectively evaluated knee undergone TKA at our hospital for both preoperative and postoperative computed tomographic (CT) evaluations. Cementing was performed with hand mixing and hand packing (HM group) and with vacuum mixing and cement gun use (VM group). We measured the area under the tibial baseplate (sclerotic and nonsclerotic sides) and compared the mean and maximum depths of cement penetration at each area.ResultsOf the 44 knees evaluated, 20 and 24 knees were in the HM and VM groups, respectively. At the center of the sclerotic side, the mean penetration depths (2.0 ± 0.7 and 2.5 ± 0.7 mm, p = 0.02) and the maximum penetration depths (4.0 ± 0.9 and 5.0 ± 1.6 mm, p = 0.02) were significantly deeper in the VM group than in the HM group. The correlation between preoperative Hounsfield unit values and mean penetration were r = –0.617 (p < 0.01) and –0.373 (p = 0.01) in the HM and VM groups, respectively.ConclusionThe cementing technique of vacuum mixing and using a cement gun allowed for deeper cement penetration compared with the hand mixing and hand packing technique, even in bone sclerotic sites.

Terahertz Spectroscopy in the Field of Food Safety: A Review

with the continuous improvement of people's living standards, food quality and safety problem has caused the wide attention of the whole society, the traditional food quality detection method has certain limitations, terahertz spectral technology (THZ) is a new spectral detection technology, its strong perspective, efficient spectral resolution ability, special fingerprint and nondestructive, in the field of food quality and safety detection has important application value. Due to the high efficiency of food quality and the need for accurate nondestructive testing, automated nondestructive testing for food quality and safety has aroused great interest from the food sector. Faster, accurate, reliable and simplified techniques are needed to classify good quality. With their unique low-energy, penetrating, rapid and non-destructive techniques are widely used as a non-destructive and cost-effective method in the food sector. This paper summarizes the principles and instruments of terahertz spectrum, and introduces the research progress of terahertz spectral detection in food, analyzes the problems in the field of food quality and safety detection, and discusses the future development trend of terahertz spectral technology.

Expert consensus on the technical specifications of the in vitro skin penetration test of cosmetic product by Franz diffusion cell

BackgroundDiffusion cell test is one of the most commonly used in vitro model to detect the percutaneous absorption of cosmetic ingredients. Although PRC State Administration of Quality Supervision and Quarantine has issued the guideline for the in vitro test method for the percutaneous absorption of drug molecules, there is still a lack of guideline for the percutaneous absorption test of cosmetic components. ObjectiveIn order to improve the standardized level and make the in vitro percutaneous absorption test of cosmetic ingredients more comparable, based on the international and domestic experience, Transdermal Drug Delivery Committee of the World Federation of Chinese Medicine Societies organized the experts to discuss and formed this consensus as reference for the percutaneous absorption test of cosmetic components. Materials and MethodsTo standardize the in vitro diffusion cell test technique for transdermal penetration of functional cosmetic ingredients, the Transdermal Drug Delivery Professional Committee of the World Federation of Societies of Traditional Chinese Medicine has organized many discussions among experts. ResultsThe expert group established this expert consensus by integrating international requirements, domestic practice, and the experience of experts. ConclusionThis consensus provides technical operation recommendations for the detection of cosmetic percutaneous permeation in in vitro diffusion cells to reduce the differences between studies. Cosmetic formulations with different compositions and types may show different release kinetics, and this consensus does not cover all possible situations.

Evaluation of Fatigue Damage Monitoring of Single-Lap Composite Adhesive Joint Using Conductivity.

The widely used adhesive joining technique suffers from the drawback of being unable to be dismantled to examine for degradation. To counteract this weakness, several structural health monitoring (SHM) methods have been proposed to reveal the joint integrity status. Among these, doping the adhesive with carbon nanotubes to make the joint conductive and monitoring its electrical resistance change is a promising candidate as it is of relatively low cost and easy to implement. In this work, resistance change to monitor fatigue debonding of composite single-lap adhesive joints has been attempted. The debonded area, recorded with a liquid penetrant technique, related linearly to the fatigue life expended. However, it correlates with the resistance change in two different trends. Scanning electron microscopy on the fracture surface reveals that the two trends are associated with distinct failure micromechanisms. Implications of these observations on the practical use of the resistance change for SHM are discussed.

Micro-optical elements from optical-quality ZIF-62 hybrid glasses by hot imprinting

Hybrid glasses derived from meltable metal-organic frameworks (MOFs) promise to combine the intriguing properties of MOFs with the universal processing ability of glasses. However, the shaping of hybrid glasses in their liquid state – in analogy to conventional glass processing – has been elusive thus far. Here, we present optical-quality glasses derived from the zeolitic imidazole framework ZIF-62 in the form of cm-scale objects. These allow for in-depth studies of optical transparency and refraction across the ultraviolet to near-infrared spectral range. Fundamental viscosity data are reported using a ball penetration technique, and subsequently employed to demonstrate the fabrication of micro-optical devices by thermal imprinting. Using 3D-printed fused silica templates, we show that concave as well as convex lens structures can be obtained at high precision by remelting the glass without trading-off on material quality. This enables multifunctional micro-optical devices combining the gas uptake and permeation ability of MOFs with the optical functionality of glass. As an example, we demonstrate the reversible change of optical refraction upon the incorporation of volatile guest molecules.

Volume Stability and Frost Resistance of High-Ductility Magnesium Phosphate Cementitious Concrete.

To address the issue of pavement cracking due to brittle concrete in road and bridge engineering, this study explores the use of high-ductility magnesium phosphate cementitious concrete (HD-MPCC) for rapid repairs. The deformation and frost properties of HD-MPCC are analyzed to assess its suitability for this application. Deformation properties were tested for HD-MPCC specimens cured in both air and water. Subsequent tests focused on the frost performance and mechanical properties after freeze-thaw cycles. A mercury penetration technique was utilized to examine the pore structure. The findings reveal that the expansion deformation of HD-MPCC increases with curing age in both air and water conditions, and the quantitative relationship between the expansion deformation and curing age of HD-MPCC was analyzed. Additionally, the freeze-thaw cycles led to a decrease in mass loss, the relative dynamic elastic modulus, the ultimate tensile strength, the ultimate tensile strain, the flexural strength, and the peak deflection. The volume fraction of harmless and less harmful pores gradually decreased as the freeze-thaw cycle increased, while the volume fraction of more harmful pores increased, resulting in a decrease in the strength, ultimate tensile strain, and peak deflection.

Bond Integrity and Microleakage of Orthodontic Bands Cemented by Glass Ionomer Cements Stored in Static Magnetic Field

Aim: Improving the band-tooth bond integrity by glass ionomer cement (GIC) is essential in orthodontic treatments. As, microleakage under bands induced enamel demineralization. Storing the dental material to updated magnets improved their mechanical properties. This research aimed to assess the microleakage of GIC after storing in a static magnetic field (SMF). Material and Methods: Forty premolars and their suitable bands were randomly classified into two main groups according to the types of GIC tested in this research; resin-modified GIC (RMGIC) and conventional GIC (CGIC). Each group was subdivided according to the exposure to SMF before polymerization into two subgroups. CGIC not exposed to SMF (CC), CGIC exposed to SMF (CM), RMGIC not exposed to SMF (LC) and RMGIC exposed to SMF (LM). SMF intensity performed was 0.225 Tesla, exposed for 48 hours at room temperature. The entire tube of RMGIC was inserted in SMF, where the powder of CGIC was stored in SMF. The microleakage under the band was evaluated under a 20× stereomicroscope by dye penetration technique at the cement band interface. Wilcoxon signed-rank test was used for data analysis, p ≤ .05. Results: The main (SD) microleakage of GIC reduced significantly ( p = .043) after being exposed to SMF from 3.1950 (0.632) mm to 1.7095 (0.1176) mm and from 0.8745 (0.1104) mm to 0.6430(0.094) mm for CGIC and RMGIC, respectively. Conclusion: Storing the CGIC powder in (0.225 T) SMF improves band-tooth bond integrity. Additionally, the preservation of RMGIC in SMF minimized the microleakage under orthodontic bands.

Study on the Improvement of Droplet Penetration Effect by Nozzle Tilt Angle under the Influence of Orthogonal Side Wind.

This study investigates the impact of varying side wind velocities and nozzle inclination angles on droplet penetration during plant protection spraying operations, focusing on citrus trees. Experiments were conducted across four wind speed levels (0, 1, 2, 3 m/s) perpendicular to the nozzle direction and seven nozzle inclination levels (0°, 8°, 15°, 23°, 30°, 38°, 45°) to evaluate droplet distribution under different spraying parameters. A baseline condition with 0 m/s wind speed and a 0° nozzle angle served as the control. Utilizing Computational Fluid Dynamics (CFD) and regression analysis techniques in conjunction with field trials, the droplet penetration was analyzed. Results indicate that at constant wind speeds, adjusting the nozzle inclination angle against the direction of the side wind can significantly enhance droplet deposition in the canopy, with a 23° inclination providing the optimal increase in deposition volume, averaging a change of +16.705 μL/cm2. Multivariate nonlinear regression analysis revealed that both wind speed and nozzle inclination angle significantly affect the droplet penetration ratio, demonstrating a correlation between these factors, with wind speed exerting a greater impact than nozzle angle. Increasing the nozzle inclination angle at higher wind speeds improves the penetration ratio, with the optimal parameters being a 23° angle and 3 m/s wind speed, showing a 12.6% improvement over the control. The model fitted for the impact of nozzle angle and wind speed on droplet penetration was validated through field experiments, identifying optimal angles for enhancing penetration at wind speeds of 1, 2, and 3 m/s as 8°, 17°, and 25°, respectively. This research provides insights for improving droplet penetration techniques in plant protection operations.

A novel troubleshooting technique for below-the-knee artery occlusions with proximal cap ambiguity: Transpedal Retrograde Wire Just Marker Technique.

Chronic total occlusions with ambiguous proximal caps pose a challenging problem in below-the-knee artery endovascular interventions. We defined a new technique for antegrade puncture and penetration of an ambiguous proximal cap in a 52-year old male patient with a non-healing wound on his right forefoot. Anterior tibial artery (ATA) was determined as the target vessel; however, its origin and course could not be determined. A retrograde guidewire (Asahi Gladius 0.018 inch, Asahi Intecc) was advanced into the distal ATA via transpedal loop following pedal loop angioplasty. This guidewire was advanced through and parked to the tibioperoneal trunk with a small distal loop at the tip. While the looped wire was held in its position as a marker for ATA ostium, a second guidewire (Asahi Gladius 0.018 inch, Asahi Intecc) with the guidance of 4F vertebral catheter (Vert Catheter, Merit Medical) successfully penetrated the ambiguous cap and subsequent target vessel revascularization was achieved with 2.5/150mm peripheral balloon angioplasty catheter (Minerva SC 0.018 inch, BrosMed Medical). Transpedal Retrograde Wire Just Marker Technique is a novel and practical technique which can be used in chronic total occlusions of below-the-knee arteries with ambiguous proximal caps.

Highly-efficient hydrogen production through the electrification of OB-SiC nickel structured catalyst: Methane steam reforming and ammonia cracking as case studies

The aim of this work is the preparation and the electrification of Ni_CeO2_Al2O3/OBSiC (Oxygen Bonded SIlicon Carbide) based foams used in two different endothermic reactions for H2 production: methane steam reforming and ammonia cracking. In particular, the heating of the catalytic foams occurs by the Joule effect, and to guarantee a uniform temperature profile in both the axial and radial direction, two different heating resistances were used. In addition, the high tortuosity together with the very high thermal conductivity of the OBSIC carrier, allow to overcome the heat and mass transfer limitations achieving a better control of the reaction behavior.Wet impregnation method was adopted for the Ni and Ce deposition, while the final catalysts was characterized through Hg penetration technique, Scanning Electron Microscope (SEM), N2 adsorption @77 K for the specific surface areas (SSA) determination and X-ray diffraction (XRD). The methane steam reforming and ammonia cracking tests were both carried out, in the same reactor, but at different space velocity values (WHSV). The results obtained are exciting, not only in terms of equilibrium approach and hydrogen production, but also in terms of energy consumption as kWh/Nm3 of H2 produced. In particular, in the case of methane steam reforming the results showed an energy consumption E [kWh/Nm3 H2] equal to 1.21 obtained at WHSV equal to 6.2 h−1, very close to the theoretical limit of 0.98 kW h/Nm3 H2. Also, for ammonia cracking, the energy consumption was very promising considering the scale of our reactor, with 1.5 kW h/Nm3 H2 obtained at a WHSV of 2.27 h−1, considering the theoretical limit equal to 0.71 kW h/Nm3 H2.

Implementing and developing multi-stage cryptography technique for low-cost long-range communication system

The requirement for a secure emergency communication system has become imperative in tandem with the industrial revolution. Additionally, the development of technology has led to increasingly robust penetration techniques that pose a threat to communication system security, leaving data vulnerable to unwanted third parties. This paper introduces a novel, powerful security approach that ensures a secure emergency communication system. Moreover, this research focuses on several cryptographic techniques among various symmetric and asymmetric ciphers, including advanced encryption standards, substitution, and transposition. The article presents an affordable and secure communication system that can transmit data over long distances with low power consumption using long-range technology. This system features a unique function that transmits updated locations, directing rescuers to the designated location.

Comparative Evaluation of Sealing Ability of Different Type of MTA as Root-End Filling Materials Using Dye Penetration Technique - An In Vitro Study

ABSTRACT Introduction: The main goal of the root-end filling material is to create a hermetic seal to protect against microbes and their by-products. Excellent biocompatibility and sealing ability are characteristics of MTA developed by Torabinejad et al. This study aimed to compare the sealing ability of different type MTA as root-end filling material using dye penetration technique. Material and Method: One-twenty (N = 120) extracted human maxillary anterior teeth were decontaminated, cleaned, and decoronated. Endodontic treatment and root-end resection were done. Then root-end cavity was prepared and filled with tested materials (N = 30). A calibrated stereomicroscope was used to evaluate linear measurement. All data were tabulated and statistically analyzed with a level of significance set at P &lt; .05. Result: This order of increasing microleaks was observed: MTA Angelus &lt; MTA Plus &lt; PRO-Root MTA &lt; Control group. There was a statistically significant difference in mean microleakage in MTA Angelus and MTA Plus groups (P = 0.040). MTA Angelus shows the least microleakage among all the bioceramic material groups. Conclusion: Although the sealing ability of MTA Angelus is superior to MTA Plus, PRO-Root MTA. MTA Plus, PRO-Root MTA could be considered an acceptable alternative to MTA Angelus in peri-radicular surgeries.

Comparative Evaluation of Penetration of Two Irrigating Solutions into Dentinal Tubules Using Diode Laser and Ultrasonic Activation: A Confocal Laser Microscopy Study Protocol

Introduction: Endodontic therapy aims to eradicate pulpal and periapical diseases by removing bacteria from root canals. Despite thorough cleaning, the smear layer obstructs canal disinfection. Root canal preparation and irrigation, particularly with sodium hypochlorite, are essential for debridement. However, conventional techniques may leave areas untreated, necessitating innovative solutions like superoxidised water and Laser-activated Irrigation (LAI) for effective treatment. Need for the Study: The effectiveness of root canal treatment is contingent upon the success of the irrigating solution and the mode used for its activation, which is directly reflected in its ability to penetrate dentinal tubules. Thus, the focus of this experimental in-vitro study is to identify the most suitable irrigating solution and an effective activation technique for better penetration into dentinal tubules. Aim: The study will evaluate and compare the penetration of Sodium Hypochlorite (NaOCl) and oxidised water irrigants into dentinal tubules using diode laser and ultrasonic activation. Materials and Methods: An experimental in-vitro study will be conducted in the Department of Conservative Dentistry and Endodontics at Sharad Pawar Dental College and Hospital, Wardha, Maharashtra, India, from August 2024 to May 2025. The approach involves categorising 60 recently extracted single-rooted teeth with fully formed apical foramina and intact occlusal morphology into six primary groups according to distinct irrigation techniques and the application of two different irrigants, resulting in 10 teeth per group. Decoronated specimens will be injected with a specific irrigant and activated using different techniques. The penetration of oxidised water into dentinal tubules by low-level laser therapy and ultrasonic activation will be evaluated and compared using confocal laser microscopy. The normality of the data will be analysed using the Kolmogorov-Smirnov test. If the data are normal, then the T-Analysis of Variance (ANOVA) test will be applied; if not, the Kruskal-Wallis test will be used at a 5% level of significance (p≤0.05).

Destabilized reporters for background-subtracted, chemically-gated, and multiplexed deep-tissue imaging.

Tracking gene expression in deep tissues requires genetic reporters that can be unambiguously detected using tissue penetrant techniques. Magnetic resonance imaging (MRI) is uniquely suited for this purpose; however, there is a dearth of reporters that can be reliably linked to gene expression with minimal interference from background tissue signals. Here, we present a conceptually new method for generating background-subtracted, drug-gated, multiplex images of gene expression using MRI. Specifically, we engineered chemically erasable reporters consisting of a water channel, aquaporin-1, fused to destabilizing domains, which are stabilized by binding to cell-permeable small-molecule ligands. We showed that this approach allows for highly specific detection of gene expression through differential imaging. In addition, by engineering destabilized aquaporin-1 variants with orthogonal ligand requirements, it is possible to distinguish distinct subpopulations of cells in mixed cultures. Finally, we demonstrated this approach in a mouse tumor model through differential imaging of gene expression with minimal background.

Multifactorial analysis and experiments affecting the effect of fog droplet penetration in fruit tree canopies.

This study examines the impact of canopy density, side wind speed, nozzle tilt angle, and droplet size on droplet penetration during plant protection spraying operations. Experiments conducted in citrus orchards evaluated how side wind speed and nozzle tilt angle influence droplet penetration across various canopy densities. A Phase Doppler Analyzer (PDA) was used to assess droplet size variations under different nozzle tilt angles and side wind speeds, yielding a multiple linear regression equation (R2 = 0.866) that links nozzle tilt angle and side wind speed with droplet size. Results showed that droplet size decreases with increasing nozzle tilt angle at a constant crosswind speed. Further experiments investigated the effects of droplet size and canopy leaf area density on droplet penetration, involving three canopy leaf area densities, four wind speeds, and six nozzle tilt angles. Droplet deposition and canopy coverage were measured under various spraying parameters, with conventional operations (0° nozzle tilt and orthogonal wind speeds) serving as controls. The study found that adjusting nozzle tilt angle and wind speed enhances droplet penetration in different canopy structures. Optimal parameters varied with leaf area density (LAD): an 18° tilt angle and 3 m/s wind speed for a LAD of 5.94 m3/m3, a 45° tilt angle and 2 m/s wind speed for a LAD of 8.47 m2/m3, and a 36° tilt angle and 3 m/s wind speed for a LAD of 11.12 m2/m3. At 1 m/s, droplet deposition followed a downward parabolic trend with changes in nozzle tilt angle, whereas at 2 m/s, deposition followed an upward parabolic trend. At a side wind speed of 3 m/s, droplet deposition remained unchanged with nozzle tilt angle but decreased with increasing canopy density. Nonlinear regression analysis indicated that leaf area density had a greater impact on deposition differences than droplet size, with droplet penetration decreasing as leaf area density increased. This study provides a reference for enhancing fog droplet penetration techniques in plant protection operations, offering practical guidelines for optimizing spraying conditions and improving pesticide use efficiency in different canopy structures.

Variability in jacking resistance of adjacent steel pipe piles under controlled pile installation

The pile bearing capacity varies even within the same site. This study aims to gain a better understanding of the effect of pile penetration techniques on the variability of bearing capacity. The study uses data from 83 jack-in test piles to explore the variations in penetration resistance at the pile head, base, and shaft. The semivariance increases with an increase of the horizontal distance, so we focus on the semivariance between 5 m range, whose error was defined as the error due to piling workmanship. The analysis shows that the errors follow a lognormal probability distribution, and the coefficient of variation (COV) in penetration resistance at the heads and bases is about 10%, while the COV in extracted resistance varies widely, with a range of 5–25%. Little difference in the variations due to piling workmanship was observed among different penetration motions, speeds, and soil types.

The Blood-brain Barrier, a Key Bridge to Treat Neurodegenerative Diseases.

As a highly selective and semi-permeable barrier that separates the circulating blood from the brain and central nervous system (CNS), the blood-brain barrier (BBB) plays a critical role in the onset and treatment of neurodegenerative diseases (NDs). To delay or reverse the NDs progression, the dysfunction of BBB should be improved to protect the brain from harmful substances. Simultaneously, a highly efficient drug delivery across the BBB is indispensable. Here, we summarized several methods to improve BBB dysfunction in NDs, including knocking out risk geneAPOE4, regulating circadian rhythms, restoring the gut microenvironment, and activating the Wnt/β-catenin signaling pathway. Then we discussed the advances in BBB penetration techniques, such as transient BBB opening, carrier-mediated drug delivery, and nasal administration, which facilitates drug delivery across the BBB. Furthermore, various in vivo and in vitro BBB models and research methods related to NDs are reviewed. Based on the current research progress, the treatment of NDs in the long term should prioritize the integrity of the BBB. However, a treatment approach that combines precise control of transient BBB permeability and non-invasive targeted BBB drug delivery holds profound significance in improving treatment effectiveness, safety, and clinical feasibility during drug therapy. This review involves the cross application of biology, materials science, imaging, engineering and other disciplines in the field of BBB, aiming to provide multi-dimensional research directions and clinical ideas for the treating NDs.