The glenoid labrum acts as a bumper, deepening glenoid concavity and amplifying the concavity-compression mechanism, and serves as the scapular attachment for glenohumeral ligaments. The role of the ...posterosuperior labrum in anteroinferior glenohumeral stability, and the role of the anterior labrum in posterior stability has been debated. The purpose of this study was to quantify the contribution of anteroinferior and posterosuperior labral tears to loss of glenohumeral stability in multiple directions.
Fourteen fresh-frozen cadaveric shoulders were tested on a custom stability ratio measurement apparatus. The peak force that was required to translate the humeral head in anterior, anteroinferior, posterior, and posteroinferior directions was measured under 5 conditions: intact labrum (n = 14), anteroinferior labral tear (n = 7), posterosuperior labral tear (n = 7), combined labral tear (n = 14), and no labrum (n = 14). The stability ratio was defined as the peak translational force divided by the compressive force. Within force-translation curves, we defined the suction cup effect as the force required to release the negative pressure created by an intact labrum.
The suction cup effect was usually present with the intact labrum and always disappeared after removal of the labrum for anterior (100% vs. 0%) and posterior (86% vs. 0%) translations (P < .001). After creation of an anteroinferior labral tear, the stability ratio for posterior direction decreased (P < .001) and the suction cup effect disappeared (P < .001). After creation of a posterosuperior labral tear, stability ratios in the anterior and anteroinferior directions decreased (P ≤ .006) and the suction cup effect disappeared (P ≤ .015). The stability ratio for anterior and anteroinferior testing was more diminished by posterosuperior labral tears than anteroinferior labral tears, and the stability ratio for posterior testing was more diminished by anteroinferior labral tears than posterosuperior labral tears.
Anteroinferior labral tears decreased posterior stability and posterosuperior labral tears decreased anterior and anteroinferior stability, largely because of loss of the suction cup effect.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To compare lesion prevalence and treatment outcomes in patients with primary and recurrent anterior shoulder instability.
Patients who were admitted to the institution with a diagnosis of anterior ...shoulder instability and who underwent arthroscopic surgery between July 2006 and February 2020 were retrospectively evaluated. Minimum follow-up duration of the patients was 24 months. The recorded data and Magnetic Resonance Imaging (MRI) of the patients were examined. Patients over 40 years of age, with a history of shoulder region fracture, inflammatory arthritis, a history of epilepsy, multi-directional instability, non-traumatic dislocation, and off-track lesions were excluded from the study. Shoulder lesions were documented and patient outcome evaluation was made with the Oxford Shoulder Score (OSS) and Visual Analog Scale (VAS).
A total of 340 patients were included in the study. The mean age of patients was 25.6 (±6.49). Recurrent instability group had significantly higher rate of Anterior Labroligamentous Periosteal Sleeve Avulsion (ALPSA) lesions compared to primary instability group (40.6% vs 24.6% respectively) (p=0.033). 25 patients (43.9%) had Superior Labrum Anterior and Posterior (SLAP) lesions in primary instability group and 81 patients (28.6%) had SLAP lesions in recurrent instability group (p=0.035). OSS increased for both primary (from 35 (16-44) to 46 (36-48)) (p=0.001) and recurrent instability groups (from 33 (6-45) to 47 (19-48)) (p=0.001). There was no significant difference between the groups regarding postoperative VAS and Oxford scores (p>0.05).
Successful results were obtained in patients younger than 40 years old with both primary and recurrent anterior shoulder instability after arthroscopic treatment. ALPSA lesion prevalence was higher while SLAP lesion prevalence was lower regarding the patients with recurrent instability. Postoperative OSS was comparable between the patient groups however failure rate was higher in the recurrent instability patients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper proposes a multi-threshold image segmentation method based on modified salp swarm algorithm (SSA). Multi-threshold image segmentation method has good segmentation effect, but the ...segmentation precision will be affected with the increase of threshold number. To avoid the above problem, the slap swarm optimization algorithm (SSA) is presented to choose the optimal parameters of the fitting function and we use levy flight to improve the SSA. The solutions are assessed using the Kapur's entropy, Otsu and Renyi entropy fitness function during the optimization operation. The performance of the proposed algorithm is evaluated with several reference images and compared with different group algorithms. The results have been analyzed based on the best fitness values, peak signal to noise ratio (PSNR), and feature similarity index measures (FSIM). The experimental results show that the proposed algorithm outperformed other swarm algorithms.
Piston slap is a major source of vibration and noise in internal combustion engines. Therefore, better understanding of the conditions favouring piston slap can be beneficial for the reduction of ...engine Noise, Vibration and Harshness (NVH). Past research has attempted to determine the exact position of piston slap events during the engine cycle and correlate them to the engine block vibration response. Validated numerical/analytical models of the piston assembly can be very useful towards this aim, since extracting the relevant information from experimental measurements can be a tedious and complicated process.
In the present work, a coupled simulation of piston dynamics and engine tribology (tribodynamics) has been performed using quasi-static and transient numerical codes. Thus, the inertia and reaction forces developed in the piston are calculated. The occurrence of piston slap events in the engine cycle is monitored by introducing six alternative concepts: (i) the quasi-static lateral force, (ii) the transient lateral force, (iii) the minimum film thickness occurrence, (iv) the maximum energy transfer, (v) the lubricant squeeze velocity and (vi) the piston-impact angular duration.
The validation of the proposed methods is achieved using experimental measurements taken from a single cylinder petrol engine in laboratory conditions. The surface acceleration of the engine block is measured at the thrust- and anti-thrust side locations. The correlation between the theoretically predicted events and the measured acceleration signals has been satisfactory in determining piston slap incidents, using the aforementioned concepts. The results also exhibit good repeatability throughout the set of measurements obtained in terms of the number of events occurring and their locations during the engine cycle.
•Six methods are used to identify piston slap events in internal combustion engines.•The number of slap events increases as the engine speed increases.•Quasi-static/transient force methods can predict slap position at lower engine speed.•The transient minimum film thickness method is more successful at higher engine speed.•The piston-impact angular duration method predicts slap events through all tests.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background:
Superior labral anterior-posterior (SLAP) lesions are common among elite gymnasts and throwing athletes. Although SLAP lesions in throwers are well-described in the literature, no study ...has described the characteristics of SLAP lesions in gymnasts. We aimed to reveal the characteristics of SLAP lesions in gymnasts by comparing the location and extension of these lesions between gymnasts and throwers.
Hypothesis:
The location and arc of SLAP lesions in gymnasts will be different from those in throwing athletes.
Study Design:
Case series; Level of evidence, 4.
Methods:
This study included 27 shoulders in 20 males and 3 females with a mean ± SD age of 20 ± 2.5 years (range, 16-25 years). We performed debridement alone for shoulders with a stable lesion. Anterior and/or posterior labral repair was added for unstable SLAP lesions depending on the extension and stability of the lesions. We investigated symptoms, onset, return to sport (based on patient records), and subjective shoulder values. SLAP lesions were evaluated through use of the Snyder classification. The location and arc of SLAP lesions were determined from surgical records and videos and described by use of the right shoulder clockface method. During the same period, 65 baseball players (65 shoulders; all males; mean age, 23 ± 7.0 years; range, 16-44 years) underwent arthroscopic SLAP surgery. We compared the location and arc of SLAP lesions between gymnasts and baseball players.
Results:
Symptoms during gymnastics included pain (100%), apprehension (48%), or catching (11%). We found that 20 shoulders had symptom onset during gymnastics, most commonly during rings events. Type II SLAP lesions were found in 17 shoulders, type III in 2 shoulders, and type IV in 8 shoulders. The mean center of SLAP lesions was at the 11:40 clockface position in 27 gymnasts and 10:40 clockface position in 65 baseball players, and the difference was statistically significant (P < .001). The mean arc of SLAP lesions was 125° in gymnasts and 140° in baseball players, and the difference was not significant. We performed debridement in 2 shoulders (7%) and labral repair in 25 shoulders (93%). After surgery, all patients returned to gymnastics. The mean subjective shoulder value was 35 (range, 10-90) preoperatively and 76 (range, 40-100) postoperatively.
Conclusion:
SLAP lesions in gymnasts were significantly located anteriorly compared with those in baseball players. All patients returned to gymnastics after arthroscopic surgery. Secure repair of SLAP lesions may be important for good surgical outcomes, because 50% of patients experienced preoperative shoulder apprehension.
Superior labrum anterior-posterior (SLAP) tears are common shoulder injuries, especially in overhead athletes. Often, initial management of these injuries is nonsurgical with focused rehabilitation. ...The purpose of this review was to evaluate the outcomes of nonsurgical management of SLAP tears in athletes.
A systematic review was performed for articles published before March 2021 using key search terms pertaining to clinical studies evaluating the nonsurgical treatment of SLAP tears in adult patients published in English-language literature. Abstracts and manuscripts were independently reviewed by 2 co-authors to determine eligibility. Return-to-play rate and return-to-prior-athletic-performance rate were determined by combining results across studies.
Five articles met the inclusion criteria. There were 244 total athletes (162 elite or higher-level athletes). The mean ages ranged from 20.3 to 38.0 years. Type II SLAP tears were most common; baseball, softball, and weightlifting were the most common sports involved. The return-to-play rate was 53.7% in all athletes and 52.5% in elite or higher-level athletes. In athletes who were able to complete their nonoperative rehabilitation program, the return-to-play rate was 78% in all athletes and 76.6% in elite or higher-level athletes. The overall rate of return to prior performance was 42.6%, which increased to 72% for those athletes who were able to complete their rehabilitation. Patients who discontinued the rehabilitation protocol in favor of surgery had an average of 8 physical therapy sessions compared with 20 sessions for patients with successful nonoperative treatment. The timing of return to play was generally less than 6 months in studies that reported it. Patient-reported outcomes, including the American Shoulder and Elbow Surgeons score and visual analog scale, all improved significantly after nonsurgical treatment. Factors associated with failure of nonsurgical management included older age, participation in overhead sports (especially baseball pitchers), traumatic injury, positive compression rotation test, concomitant rotator cuff injury, longer baseball career, longer symptomatic period, and the presence of a Bennett spur.
Overall, nonoperative treatment of SLAP tears in athletes can be successful, especially in the subset of patients who are able to complete their rehabilitation program before attempting a return to play. Although nonoperative treatment should be considered the first line of treatment for most SLAP tears, there are some factors that may be associated with failure of conservative treatment; therefore, further high level, prospective studies would be beneficial to identify those athletes most likely to respond favorably to nonoperative treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Every day, billions of fingerprint images are captured worldwide through the extensive deployment of slap-fingerprint acquisition devices, serving e-governance programs and bolstering national border ...security. Several studies from national ID programs, like UIDAI and NIST, have indicated that about 2% of the user population may lack usable fingerprints. Finger knuckle patterns are inherently presented during such slap-fingerprint acquisition and can be simultaneously acquired without imposing any additional inconvenience on the users. Leveraging these finger knuckle patterns can enable not only significant improvement in identification accuracy but also enhance overall protection and facilitates smoother traffic flow. This paper develops the first such finger-knuckle-assisted fingerprint identification system for real-world applications. We systematically develop automated finger knuckle detection and segmentation algorithms, for multiple knuckles and under complex illumination, for such contactless images from the deployed slap fingerprint devices. Currently, available algorithms offer limited performance for such images, and therefore this paper proposes a new approach to more accurately match such knuckle images. Our experimental results illustrate the significant performance improvement over existing knuckle matching algorithms, and further by incorporating dynamic fusion capabilities. This paper also introduces the first joint finger-knuckle and fingerprint database, from 120 different subjects, in the public domain to advance further research and development efforts needed in this area.
Glenoid superior biceps-labral pathology diagnosis, treatment, and outcomes are an evolving area of shoulder surgery. Historically, described as superior labrum anterior posterior (SLAP) tears, these ...lesions were identified as a source of pain in throwing athletes. Diagnosis and treatments applied to these SLAP lesions resulted in less than optimal outcomes in some patients and a prevailing sense of confusion. The purpose of this paper is to perform a reappraisal of the anatomy, examination, imaging, and diagnosis by the American Shoulder and Elbow Surgeons/SLAP biceps study group. We sought to capture emerging concepts and suggest a more unified approach to evaluation and identify specific needs for future research.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper proposes a new method for encryption of RGB color images by combining two encryption approaches: the spatial approach and the transformation approach. The proposed method uses the 3D ...fractional modified Henon map (3D FrMHM) and the discrete fractional Krawtchouk moments (FrDKM). We have also proposed a new hybrid optimization algorithm (H-SSAOA) to optimize the parameters of the proposed Henon map and the parameters of the Krawtchouk fractional moments. This algorithm is based on the hybridization of two metaheuristic algorithms: the "Salp Swarm Algorithm" (SSA) and the "Arithmetic Optimization Algorithm" (AOA). The simulation results reveal the optimization efficiency of the proposed hybrid algorithm H-SSAOA compared to other meta-heuristic algorithms and the efficiency of the suggested encryption method for encrypting RGB color images in terms of sensitivity to the security key and resistance to different attacks.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The S-layer proteins are a class of self-assembling proteins that form bi-dimensional lattices named S-Layer on the cell surface of bacteria and archaea. The protein SlpA, which is the major ...constituent of the
S-layer, contains in its C-terminus region (SlpA
), a protein domain (named here as SLAP
) responsible for the association of SlpA to the bacterial surface. SLAP
was adapted for the development of a novel affinity chromatography method: the SLAP
-based affinity chromatography (SAC).
Proteins with different molecular weights or biochemical functions were fused in-frame to the SLAP
and efficiently purified by a
-derived affinity matrix (named Bio-Matrix or BM). Different binding and elution conditions were evaluated to establish an optimized protocol.
The binding equilibrium between SLAP
and BM was reached after a few minutes of incubation at 4°C, with an apparent dissociation constant (K
) of 4.3μM. A reporter protein (H6-GFP-SLAP
) was used to compare SAC protein purification efficiency against commercial immobilized metal affinity chromatography. No differences in protein purification performance were observed between the two methods. The stability and reusability of the BM were evaluated, and it was found that the matrix remained stable for more than a year. BM could be reused up to five times without a significant loss in performance. Additionally, the recovery of bound SLAP-tagged proteins was explored using proteolysis with a SLAP-tagged version of the HRV-3c protease (SLAP
). This released the untagged GFP while the cut SLAP
and the SLAP
were retained in the BM. As an alternative, iron nanoparticles were linked to the BM, resulting in BM
. The BM
was successfully adapted for a magnetic SAC, a technique with potential applications in high-throughput protein production and purification.
The SAC protocol can be adapted as a universal tool for the purification of recombinant proteins. Furthermore, the SAC protocol utilizes simple and low-cost reagents, making it suitable for in-house protein purification systems in laboratories worldwide. This enables the production of pure recombinant proteins for research, diagnosis, and the food industry.
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