Efficient Fog-Harvesting Origami Fan.

Fog harvesting represents a promising strategy to address the global freshwater shortage. To enhance the water collection efficiency, diverse geometric structures that can effectively drive water droplet movement are essential. Inspired by the Livistona chinensis leaf, which naturally facilitates directional droplet motion through its unique gradually varying V-groove structure, we have developed a novel origami fan structure for fog harvesting through theoretical analysis. A key feature is that we can modulate the speed of droplet transport by adjusting the opening angle of the V-shaped grooves positioned at the outer circumference. Interestingly, the water collection efficiency exhibits a linear correlation with the opening angle. The highest efficiency of the origami fan can reach 5.75 times that of the control group calculated by the projected area and 3.76 times that of the control group calculated by the real area, showcasing its significant potential for enhancing water collection from fog. The simulations demonstrate that the hollow structure enhances the condensation rate of droplets, the geometric gradient of the gradual-variation V-groove drives the condensed droplets to move rapidly on the surface, and the Janus membrane permits the aggregated droplets to transit to the fan's rear side. The synergistic action of these three components ensures a clean surface for the subsequent water-collecting cycle, contributing to the high fog-harvesting efficiency. Given its simple fabrication and superior water transfer efficiency, the origami fan holds substantial promise for widespread application in the field of droplet manipulation.

Ratio of Tibial Tubercle-Trochlear Groove Distance to Patellar Width as a Predictor of Patellar Dislocation: Analysis of Individualized Tibial Tubercle Lateralization Parameters.

Background: Available conventional tibial tubercle lateralization (TTL) parameters fail to account for individual patient size or anatomy. Purposes: To evaluate the predictive ability of individualized TTL parameters and clarify the best predictor of patellar dislocation (PD) and to determine the relationship of the best predictor with other risk factors of PD with quadriceps isotonic contraction. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: A total of 15 patients with PD (28 knees) and 14 controls (28 knees) underwent 4-dimensional computed tomography, and the image with the knee fully extended and quadriceps isotonically contracted was selected for evaluation. The following TTL parameters were measured on the images: tibial tubercle-trochlear groove (TT-TG) distance, tibial tubercle-Roman arch distance, and tibial tubercle-posterior cruciate ligament distance, as well as their ratios to femoral condylar width and patellar width (PW). In addition, the following parameters were measured: Insall-Salvati ratio, Blackburne-Peel ratio, Caton-Deschamps ratio, modified Insall-Salvati ratio, bisect offset index, congruence angle, lateral patellar tilt, lateral trochlear inclination, sulcus depth, sulcus angle, trochlear groove medialization, patella-patellar tendon angle, patellofemoral axis angle (P-FAA), patellar articular facet-patellar tendon angle, patellar articular facet-femoral axis angle (PA-FAA), and patellar shape according to Wiberg type. The area under the receiver operating characteristic curve (AUC) was calculated to access the diagnostic accuracy of the TTL parameters for PD, and the TTL parameters with high diagnostic ability were evaluated for correlation with the remaining parameters. Results: The TT-TG/PW ratio had the best diagnostic ability for PD (AUC = 0.890). The TT-TG/PW ratio was positively correlated with bisect offset index, congruence angle, lateral patellar tilt, P-FAA and PA-FAA (r = 0.610, 0.465, 0.635, 0.553 and 0.418, respectively; P≤ .027 for all), and TT-TG/PW ratio was greater in knees with type II versus type III patella (P = .017). Conclusion: With the knee fully extended and quadriceps isotonically contracted, the TT-TG/PW ratio was found to be the best predictor of PD and reflected individualized TTL, which helps with clinical preoperative planning.

A Comparative Study of Correction of Caudal Septal Deviations.

BACKGROUND: There are multiple surgical approaches for the correction of caudal septal deviation. OBJECTIVES: To compare the surgical outcomes of the widely used techniques of correction of caudal septal deviation. MATERIALS AND METHODS: In a prospective study done over a period of 3 years, 36 patients with caudal septal deviation were selected and randomly divided into 3 groups of 12 each who underwent surgery by the following techniques: Group A - Swinging Door technique. Group B- Tongue-in-groove technique. Group C- The cutting and suture technique with unilateral bony batten grafting. The preoperative and postoperative (at 6 months) NOSE score, anterior rhinoscopy and subjective assessment were used to measure surgical outcomes and the techniques were compared. RESULTS: Out of the 36 patients, the mean NOSE score preoperatively and postoperatively were as follows. For Group A- 72.5 and 23.33. For Group B- 73.75 and 19.17. For Group C- 72 and 22. A significant improvement of mean 49.17, 54.58 and 50.00 with p-value of < 0.05 respectively. Anterior rhinoscopy done at 6 months postoperatively showed that 30 patients (83%) had a straight septum while 6 patients (17%) had some residual deviation. Subjective patient satisfaction was "much improved" in 17 (47.2%) patients, and "improved" in 19 (52.8%) patients. Four patients had postoperative synechia which were managed conservatively. CONCLUSION: Surgical correction of caudal septal deviation resulted in significant improvements in nasal airway. The tongue-in -groove technique was found to be the most effective among the three.

Sex prediction according to digital analysis of the morphological characteristics of maxillary posterior teeth in a Pakistani population.

Objective: Researchers have examined several dental characteristics to identify differences in tooth morphology between males and females in various populations. Nevertheless, no research has been undertaken to ascertain sexual dimorphism and develop a sex prediction model by using the groove pattern, cusp number and occlusal pattern in any population group. Therefore, this study accessed the sexual differences and the ability to predict sex according to these characteristics of maxillary teeth in the Pakistani community. Method: A total of 130 dental casts were selected (65 each from males and females). Digital images of the occlusal surface of the maxillary first premolar, second premolar and first molar were captured with a Canon Powershot A2200 14.1 MP digital camera with 4× optical zoom. Cusp number, groove pattern and occlusal pattern were recorded for each tooth type. Data were analysed with chi-square tests and logistic regression analysis. Results: The groove pattern and occlusal pattern of the maxillary first premolar and first molar showed significant sexual dimorphism (p < 0.05). The cusp number of the maxillary first molar also displayed a statistically significant difference between males and females (p < 0.05). The sex prediction accuracy was 76.7% for the training samples and 70% for the test samples. Conclusion: We observed significant sexual dimorphism in the groove pattern and the occlusal pattern of the maxillary first premolar and maxillary first molar teeth, as well as the cusp number of the maxillary first molar teeth. The prediction model demonstrated good accuracy, at 76.7%, and hence can be used for sex prediction in the Pakistani population.

Study on the electrochemical and spectroscopic characteristics of holmium ion and its interaction with DNA.

Metal ion-DNA interactions play a crucial role in modulating the structure and function of genetic material in the natural environment. In this study, we report on the favorable electrochemical activity of holmium(III) (Ho3+) on a glassy carbon electrode (GCE) and its interaction with double-stranded DNA. The interaction between DNA and Ho3+ was investigated for the first time using cyclic voltammetry and differential pulse voltammetry. The electrochemical behavior of Ho3+ ions on a GCE exhibited a reversible electron transfer process, indicative of its redox activity. A linear correlation between the peak current and the square root of the scan rate was observed, suggesting a diffusion-controlled kinetic regime for the electrochemical process. Additionally, fluorescence and absorption spectroscopy were employed to confirm the binding of Ho3+ to DNA. Our findings demonstrate that, at pH 7.2, specific DNA bases and phosphate groups can interact with Ho3+ ions. Moreover, electrochemical measurements suggest that Ho3+ ions bind to DNA via a groove binding mode, with a calculated binding ratio of 1:1 between Ho3+ and DNA. Notably, under optimal conditions, an increase in the amount of DNA leads to a significant reduction in the current intensity of Ho3+ ions.

Palatal groove associated with periodontal lesions: a systematic review illustrated by a decisional tree for management.

BACKGROUND: Palatal groove represents a relatively uncommon developmental root anomaly, usually found on the palatal aspect of maxillary incisors. While its origin is controversial, its presence predisposes to severe periodontal defects. AIM: This study aimed to provide a systematic review of the literature focusing on the varied diagnostic techniques and treatment modalities for periodontal lesions arising from the presence of palatal groove. Based on the existing evidence and knowledge, the study also provides a comprehensive decisional tree, guiding clinicians in the challenging decision-making process face to a palatal groove. METHODS: The literature search was conducted on Medline and Cochrane databases by two independent reviewers, who also performed the screening and selection process, looking for English written articles reporting on diagnosis and management (all treatment approaches) of periodontal lesion(s) associated with a palatal groove. Based on this literature, a comprehensive decisional tree, including a standardized palatal groove evaluation and tailored treatment approaches, is proposed. Moreover, a clinical case is described to demonstrate the practical application of the developed decisional tree. RESULTS: Over a total of 451 articles initially identified, 34 were selected, describing 40 patients with 40 periodontal lesions associated with palatal grooves. The case report illustrates a deep, large, circumferential intra-bony defect on the palatal side of the tooth #22 associated with a shallow, moderately long palatal groove in an 18-year-old male patient. Following reevaluation, a single flap surgery was deemed necessary, combined with a regenerative procedure. At 2 years post-treatment, the tooth #22 is healthy, in a functional and esthetic position. The decision-making process, based on local and systemic patient's conditions, should allow an early and precise diagnosis to prevent further complications and undertake an adequate treatment. CONCLUSION: Palatal grooves are relatively rare; however, they are frequently associated with severe periodontal defects. The identification, diagnosis, prompt, and tailored management of the associated lesion is essential to mitigate potential periodontal and endodontic complications related to the presence of palatal groove. SYSTEMATIC REVIEW REGISTRATION: [ https://www.crd.york.ac.uk/prospero/ ], identifier [C CRD42022363194].

Research on jet electrochemical machining with coaxial megasonic assistance.

In order to address the problem of poor localization in electrochemical machining (ECM), a coaxial megasonic assisted jet ECM method was proposed. Based on theoretical analysis, experiments were conducted to compare the effects of various electrolyte flow rates, electrolytic voltage and megasonic power levels on pit ECM. The results indicate that, in the range of experimental parameters, the increase of electrolyte flow rate and megasonic power can increase the machining depth, so as to improve the depth-diameter ratio of ECM pits. The use of coaxial megasonic-assisted jet ECM can enhance the depth-diameter ratio of etched pits compared to the without megasonic one. When applying a megasonic power of 22 W, the dimensions of the ECM pit were measured as 0.81 mm in depth and 5.73 mm in diameter, resulting in an depth-diameter ratio of 0.140. Under the same conditions, without megasonic assistance, the pit diameter is reduced to 0.65 mm while the pit depth increases to 6.36 mm, resulting in a depth-diameter ratio of 0.102. Additionally, The results also demonstrate that, the increase of electrolytic voltage makes the depth to diameter ratio of pit further increase on the original basis. With an electrolyte flow rate of 0.9 L/min and a megasonic power of 22 W, the use of electrolysis voltage of 50 V increased the depth-diameter ratio of etched pits to 0.173. Using the above preferred parameters, electrolytic milling of the wide groove is carried out. The depth-diameter ratio of the wide groove is increased from 0.039 to 0.059 by appending coaxial megasonic. This further verified the effectiveness of the coaxial megasonic-assisted jet ECM method.

Analyzing Alignment Error in Tibial Tuberosity-Trochlear Groove Distance in Clinical Scans Using 2D and 3D Methods.

BACKGROUND: Tibial tuberosity-trochlear groove distance (TT-TG) is often used as a primary metric for surgical decision-making in the treatment of patellofemoral instability (PFI), particularly when considering tibial tubercle transfer. Although TT-TG has high interrater reliability, it is prone to measurement differences caused by the alignment of the patient's leg in a scanner gantry, potentially influencing surgical decision-making. Quantification of this error within the clinical literature remains limited. PURPOSE: To quantify and specify the error in TT-TG caused by leg-scanner alignment by using detailed topographical landmarks and 3-dimensional (3D) analysis of computed tomography scans of patients with PFI. STUDY DESIGN: Controlled laboratory study. METHODS: Three-dimensional models of knees with PFI were created from computed tomography scans and used to identify TT-TG landmarks. TT-TG was measured using the established 2-dimensional (2D) and 3D methods. A model to estimate the differences between these 2 methods was created, and the orientation of the patients' legs in relation to scanner longitudinal axis was measured to validate this model via linear regression. Interrater reliability was calculated via intraclass correlation coefficients (ICC). RESULTS: A total of 44 knees of patients with PFI were analyzed. Differences between the 2D and 3D methods ranged from -4.0 to 14.7 mm (mean ± SD, 2.7 ± 4.1 mm) with a root mean square difference of 4.8 mm. The TT-TG distance of the 2D method (19.8 ± 7.2 mm) was significantly (P = .045) longer than that of the 3D method (17.1 ± 4.9 mm). The variance of the 2D method was significantly larger than that of the 3D method. In total, 13 (29.5%) of the knees had a difference of >5 mm between 2D and 3D TT-TG. The estimation model had an adjusted r2 value of 1.00 and a resulting root mean square difference of 0.21 mm. 3D TT-TGs interrater reliability was good to excellent (ICC, 0.94 [95 CI%, 0.81-0.98]). CONCLUSION: 3D TT-TG can be used to correct scanner-leg alignment errors, some of which are substantial when using only 2D TT-TG measurements. CLINICAL RELEVANCE: The findings in this study suggest a need for caution and awareness of the potential effects of differences in alignment of the axes of the leg and scanner when using purely 2D TT-TG as a basis for surgical planning.

Micro-Computed Tomographic Analysis of Radicular Dentin Thickness in Mandibular Second Molars Across Diverse Anatomic Root Variations: Identifying Potential Danger Zones.

INTRODUCTION: This study aimed to investigate radicular dentin thicknesses in mandibular second molars (MSMs), considering variations in root configuration and the morphology of the pulp chamber floor (PCF). The types of radicular grooves and potential danger zones were also identified. METHODS: A total of 149 MSMs were scanned with micro-computed tomographic imaging and classified into 4 groups according to root fusion and PCF morphology as follows: (1) 45 with fused roots and C-shaped PCFs, (2) 45 with fused roots and non-C-shaped PCFs, (3) 14 with a single canal, and (4) 45 with separated roots. The first 2 groups were subdivided into Ω-shaped, U-shaped, and V-shaped radicular groove subgroups. Measurements included minimum and mean dentin thickness from the start of the radicular groove or root bifurcation extending 5 mm apically, the ratio of outer to inner dentin thickness, and the distribution of dentin thickness. RESULTS: Ω-shaped and U-shaped subgroups showed significant thinner minimum inner wall thickness than V-shaped subgroups at 2-5 mm from the starting point of the radicular groove in both C-shaped and non-C-shaped pulp floor categories (P < .05). The mesial roots of separated rooted MSMs showed significant thinner dentin than a non-C-shaped floor regarding minimum and mean inner thickness and mean outer thickness (P < .05). Teeth with a single canal had significantly thicker walls compared with the other 3 groups. CONCLUSIONS: In MSMs, caution must be exercised, especially in the presence of Ω-shaped and U-shaped grooves in C-shaped roots and around the root furcation of separated roots.

Comparative study of the stridulatory groove in species of Triatoma (Hemiptera: Reduviidae) from Mexico.

The stridulation in the subfamily Triatominae has been identified as a means of communication between species, produced by the friction of the proboscis on the prosternal stridulatory groove. Despite its biological significance, this phenomenon remains understudied, with the signal's production seemingly contingent upon the morphology of the stridulatory groove. In this study, we examined the morphology of stridulatory grooves in females and males of five species and two subspecies of Mexican triatomines using morphometric and scanning electron microscopical analysis. Our findings reveal that all analyzed species exhibit triangular-shaped stridulatory grooves with parallel ridges covering the entire groove, bordered on each side, and covered with setae. Surprisingly, we observed noticeable differences in the number of ridges and inter-ridge distance between the species Triatoma lecticularia and Triatoma rubida (p < 0.001 and p < 0.009, respectively), indicating sexual dimorphism in this aspect, a phenomenon not previously reported in the morphology of this structure. Our findings shed light on the intricate morphology of the stridulatory groove in Mexican triatomines, suggesting potential implications for their behavior and intra-specific communication.

Unveiling the multifaceted interactions of antitumor drug mitoxantrone with ct-DNA through biophysical and in silico studies.

Mitoxantrone, an anthraquinone derivative, is a widely used anticancer drug with its well-known ability to engage in complex interactions with DNA. Although known for its intercalating ability, the enigma surrounding its binding modes with DNA persists. The existing corpus of literature primarily focuses on mitoxantrone-DNA interactions with short DNA sequences, thereby yielding insights into its interactive nature is limited to this specific sequence. This study aims to elucidate the diverse modes with which mitoxantrone interacts with calf thymus DNA using a combination of spectroscopy, calorimetry and in silico studies. The findings from spectroscopic, calorimetric and molecular dynamic results in correlation with existing literature, unveil a fascinating narrative: mitoxantrone intercalates at lower concentrations but promotes condensation at higher concentrations. Although intercalation with side chains positioned in the minor/major groove is the major binding mode in GC-rich sequences, molecular modelling studies hint at an alternative binding mode in AT-rich sequences where it exclusively displays pure electrostatic interaction. These findings underscore the pivotal role of both drug structure and base sequence in dictating binding mode and affinity. Such insights not only deepen the understanding of structure-activity relationships but also hold promise for guiding future drug design strategies.

Femoral anteversion angle is more advantageous than TT-TG distance in evaluating patellar dislocation: A retrospective cohort study.

PURPOSE: The purpose of this study is to report the parameter characteristics of the femoral anteversion angle (FAA) and tibial tubercle-trochlear groove (TT-TG) distance in patients with patellar instability compared to healthy individuals and to evaluate their reliability in predicting patellar dislocation, providing potential indications for osteotomy. METHODS: A retrospective collection of consecutive patients with patellar instability constituted the study group, while individuals without patellofemoral disorder served as the control group. Measurement of the FAA and TT-TG distance were conducted by lower extremity computed tomography scans and knees with true patellar dislocation were recorded. The diagnostic capability of the FAA and TT-TG distance was assessed using receiver operating characteristic curves and area under the curve (AUC), determining the pathological values by sensitivity and specificity. RESULTS: The FAA (21.6 ± 9.0°) and TT-TG distance (20.1 ± 4.8 mm) in the study group were significantly greater than the control group (10.6 ± 7.9° and 15.6 ± 4.6 mm, respectively) (p < 0.001). The AUCs for patellar dislocation were 0.869 for FAA and 0.712 for TT-TG distance, with pathological cut-off values of 18.2° and 18.2 mm, respectively. The odds ratios for FAA and TT-TG distance were 1.185 and 1.125, respectively (p < 0.05). CONCLUSIONS: Patients with patellar instability exhibited significantly greater FAA and TT-TG distance compared to healthy individuals. The FAA demonstrated superior predictive capability for patellar dislocation compared to the TT-TG distance. The FAA (>18.2°) measured by surgical transepicondylar axis and TT-TG distance (>18.2 mm) were the potential pathological thresholds. Additionally, an increase of 1° in FAA and 1 mm in TT-TG distance was associated with a 18.5% and 12.5% increased risk of patellar dislocation, respectively. Surgeons should be aware of the risk of patellar dislocation associated with rotational malalignment. LEVEL OF EVIDENCE: Level III.

Bilateral cranioorbital foramina (Hyrtl foramina): crucial anatomical findings in the management of giant olfactory groove meningioma - a case report and literature review.

Presence of bilateral cranio-orbital foramina, AKA Hyrtl foramina is rare yet existing. They carry the risks of retinal artery emboli due to reflux embolization for the neurovascular interventionalists, navigating complexities in olfactory groove meningioma management. A 59-year-old woman with progressive frontal lobe syndrome presented a large olfactory groove meningioma primarily supplied by bilateral sphenopalatine arteries together with bilateral anterior cerebral arteries, necessitating risky preoperative embolization and meticulous resection. This case underscores the intricate nature of vascular supply in frontal skull base tumors, emphasizing the need for multidisciplinary approaches, thorough preoperative planning, and detective research to optimize treatment outcomes.

Case Report: Left atrial dissection after mitral valve replacement: intraoperative management under TEE guidance.

Left atrial dissection (LatD) is a very rare complication of cardiac surgery, but it is relatively more common in mitral valve surgery. Transesophageal echocardiography (TEE) plays an important role in timely detection of LatD and accurate assessment of the condition, which are key factors in determining the patient's prognosis. There are two different treatment options for patients with or without circulatory crisis caused by dissection hematoma, namely surgical management and conservative treatment. In this report, we used TEE to quickly detect the cause and severity of LatD, which assisted the surgeon in making appropriate surgical decisions. The patient was successfully surgically treated for LatD.

Medial orientation of the trochlear groove is a strong indicator of high-grade trochlear dysplasia.

PURPOSE: The objective is to evaluate the orientation of the trochlear groove in patients with objective patellar instability (OPI) compared to a control group. The hypothesis is that the trochlear groove angle (TGA) is correlated with the severity of the trochlear dysplasia. METHODS: From 2019 to 2023, magnetic resonance imaging of 82 knees with OPI were compared with 82 control knees. TGA quantified the angle between the femoral anatomical axis and the trochlear groove. The intraclass correlation coefficient for TGA was evaluated. Central spur in the sagittal plane (CSSP) and cranial trochlear orientation (CTO) angle were also measured. TGA, CSSP and CTO were compared between the two groups. A TGA subgroup analysis separating the OPI group into low-grade (CSSP < 5 mm or negative CTO) and high-grade dysplasia (CSSP ≥ 5 mm or positive CTO) was also performed. RESULTS: A significant difference (p < 0.001) was found between the TGA of the OPI group (mean [SD], 11.3 [3.7]°) and the control group (4.2 [2.5]°). TGA for patients with high-grade dysplasia (11.9 [3.8]°) was significantly higher than patients with low-grade dysplasia (9.6 [3.9]°). CONCLUSION: Patients with OPI have a TGA of 11°, compared to the control group, which exhibits a TGA of 4°. The femoral mechanical axis can be considered an appropriate threshold for separating these two groups. Furthermore, TGA is correlated with the severity of dysplasia. STUDY DESIGN: Case-control study. LEVEL OF EVIDENCE: Level III.

Palatogingival Groove: The Known-unknown Devourer.

Aim: This case report aims to describe the management of a maxillary lateral incisor with a palatogingival groove (PGG) associated with a complex lesion. Background: The PGG is a rare developmental anomaly that involves the lingual surface of the maxillary incisors and extends for varying distances and depths on the root surface. This anomaly is usually inconspicuous and funnel-shaped, which forms a niche where bacterial plaque and calculus can accumulate to levels significant for pathological changes resulting in endodontic and periodontal lesions. These grooves are easily overlooked as etiologic factors, as they are concealed by the periodontal tissues. Case description: This paper describes the successful management of a rare case of maxillary lateral incisor with an accessory root, two canals, and a complex or type III PGG with a endodontic-periodontic lesion using a multidisciplinary approach. Conclusion: Recognizing PGG as the initiator of pathology is critical for the successful treatment and favorable prognosis of the affected tooth. Clinical significance: This case report highlights the importance of three-dimensional (3D) imaging using cone beam computed tomography (CBCT) that can provide accurate and sensitive information to assess and plan the treatment of the teeth with PGG. It also emphasizes that with the development of newer materials and diagnostic tools, clinicians need a detailed understanding of the characteristics, treatment, and prognosis of PGG to successfully manage the condition. How to cite this article: Gupta S, Tandon S, Rathore AS, et al. Palatogingival Groove: The Known-unknown Devourer. Int J Clin Pediatr Dent 2024;17(S-1):S95-S99.

More negative sagittal tibial tuberosity-trochlear groove distances are correlated with larger patellofemoral chondral lesion size.

PURPOSE: The purpose of this study is to assess the association between sagittal tibial tuberosity-trochlear groove (sTT-TG) distance and patellofemoral chondral lesion size in patients undergoing cartilage restoration procedures. METHODS: A retrospective cohort analysis of patients who underwent an osteochondral allograft transplantation or matrix-induced autologous chondrocyte implantation in the patellofemoral compartment, from 2010 to 2020, were included if they had patellofemoral high-grade lesions, magnetic resonance imaging (MRI) and minimum 2-year follow-up. The preoperative sTT-TG distance was measured independently on axial T2-weighted MRI sequences by two authors, each at least two weeks apart. Intraoperative lesion size was reported according to operative report measurements by the attending surgeon. An interclass correlation coefficient (ICC) was calculated to assess intra- and inter-rater reliability, and categorical data analysis and linear regression models were used to assess the relationship between sTT-TG and lesion size. RESULTS: A total of 80 patients (50 females) with a mean age of 31.5 ± 10.4 years, body mass index of 27.0 ± 5.9 kg/m2 and follow-up of 61.5 ± 21.4 months were included. A total of 107 lesions were present: 63 patients with unipolar (patella = 41, trochlea = 22) and 22 with bipolar lesions. The mean MRI defect size was 1.6 ± 1.0 cm2 and the mean intraoperative defect size was 3.8 ± 2.4cm2. Intra- (ICC: 0.99,0.98) and inter-rater reliability (ICC: 0.96) were excellent for both MRI defect size and sTT-TG measurements. The mean sTT-TG was -4.8 ± 4.9 mm and was significantly inversely related to MRI defect size (-0.45, p < 0.01), intraoperative patellar lesion size (-0.32, p = 0.01), total lesion area (-0.22, p = 0.04), but not trochlear lesion size (-0.09, p = 0.56). Multivariable regression demonstrated a more negative sTT-TG remained an independent variable correlated with larger MRI-measured patellofemoral defect sizes and intraoperative patellar lesions. CONCLUSION: A more negative sTT-TG was an independent variable correlated with larger patellofemoral lesions in patients undergoing patellofemoral cartilage restoration. LEVEL OF EVIDENCE: Level III, Diagnostic.

The Prediction and Evaluation of Surface Quality during the Milling of Blade-Root Grooves Based on a Long Short-Term Memory Network and Signal Fusion.

The surface quality of milled blade-root grooves in industrial turbine blades significantly influences their mechanical properties. The surface texture reveals the interaction between the tool and the workpiece during the machining process, which plays a key role in determining the surface quality. In addition, there is a significant correlation between acoustic vibration signals and surface texture features. However, current research on surface quality is still relatively limited, and most considers only a single signal. In this paper, 160 sets of industrial field data were collected by multiple sensors to study the surface quality of a blade-root groove. A surface texture feature prediction method based on acoustic vibration signal fusion is proposed to evaluate the surface quality. Fast Fourier transform (FFT) is used to process the signal, and the clean and smooth features are extracted by combining wavelet denoising and multivariate smoothing denoising. At the same time, based on the gray-level co-occurrence matrix, the surface texture image features of different angles of the blade-root groove are extracted to describe the texture features. The fused acoustic vibration signal features are input, and the texture features are output to establish a texture feature prediction model. After predicting the texture features, the surface quality is evaluated by setting a threshold value. The threshold is selected based on all sample data, and the final judgment accuracy is 90%.

A profound study of damage behavior for Al 2024-T3 alloy worksheet produced by constrained groove pressing in the superior practical condition.

Constrained groove pressing (CGP) process is one of the most efficient and novel methods of severe plastic deformation to manufacture ultra-fine sheet metal. The present research work is related to the study of CGP process of 2024-T3 Aluminum alloy sheet. The empirical and numerical simulation of CGPed- specimens have been examined at both room and elevated temperatures. In order to simulate the constrained groove pressing process in Abaqus software, the Johnson-Cook material model has been employed. The geometrical variables of the CGP process include the teeth number, teeth angle, and sheet thickness, and the criterion for the superiority of the numerical test is the maximum reduction of two equivalent strain and equivalent force factors, simultaneously. To determine the weight's coefficients of the target factors and select the superior test, the Shannon's Entropy and Simple Additive Weighting (SAW) methods have been used, respectively. After validating the numerical findings, the variation of damage parameter, stress triaxiality and the equivalent plastic strain distribution in the superior practical condition have been evaluated in detail. Based on the Entropy-SAW hybrid technique, the weight's coefficients of equivalent strain and equivalent force target factors were computed to, in turn, 0.38 and 0.62. Also, the results revealed that the CGP process could not be performed at room temperature based on high damage evolution. But, at elevated temperature, the damage parameter (D) doesn't exceed 0.26. Also, the maximum stress triaxiality and equivalent plastic strain (PEEQ) at this process temperature reached to 0.5 and 0.1, respectively.