in locked dislocation of the shoulder, instead of reducing back to the glenoid, the humeral head remains incarcerated on the glenoid in a locked fashion. This clinical situation is fairly uncommon. It is essential to conduct an individual evaluation of each patient to determine the appropriate treatment. the aim of this study was to evaluate the functional outcomes of reverse total shoulder arthroplasty (rTSA) in the treatment of locked shoulder dislocation. patients with locked shoulder dislocation who underwent reverse shoulder prosthesis surgery and were admitted to our center between 2007 and 2023 were reviewed. The primary outcome was the Constant score. Secondary outcomes included the adjusted Constant, UCLA and DASH scores. Additionally, any signs of radiologic loosening were also documented. the series consisted of 10 patients, six men and four women, with a mean age of 68.0 years. The average time from the traumatic injury to surgery was 7.5 months. All patients showed improved Constant, Adapted Constant, UCLA, and DASH scores compared to their preoperative values. When comparing the outcomes of chronic posterior and anterior dislocations, no differences in functional outcomes or shoulder motion were observed after rTSA implantation. There were no complications during or after surgery. The results of the present study have shown that patients with locked shoulder dislocation can achieve reliable short-term functional results when treated with rTSA. This proceduredecreases pain, improves functionality and enhances patient satisfaction. IV.
Side-locked headache is commonly regarded as a warning sign for secondary intracranial pathology; however, its musculoskeletal causes may be underrecognized. We report a series of seven patients with strictly unilateral headache consistently and temporally associated with the habitual clamping of a mobile phone between the neck and shoulder during hands-free multitasking. The headache was nonthrobbing, lacked migrainous or cranial autonomic features, and was reproducible with cervical palpation or sustained neck movements. Neurological examination and neuroimaging were normal in all cases. Cervical muscle tenderness, spasm, and trigger point-mediated referred pain were prominent findings. Conservative management focusing on avoidance of the implicated posture, posture correction, and physiotherapy was associated with substantial improvement or complete resolution in all patients. This series highlights neck-shoulder mobile phone clamping as a common posture-related trigger for cervicogenic or myofascial headache and underscores the importance of assessing smartphone-handling behaviors in patients with unilateral headache. These findings are hypothesis-generating and do not establish causality.
Agile motor action requires rapid switching between motor states while maintaining stability. Because motor output combines fast and slow muscle fibers with distinct kinetics, prolonged slow-fiber activation can broaden burst envelopes and blur within-cycle transitions, limiting temporal precision. Here, we show that agility training improves locomotor timing by selectively compressing the activity of slow motor neurons through enhancing commissural inhibition. In adult zebrafish, training increased locomotor stability and reshaped cycle structure in vivo, shortening the contraction phase while extending relaxation. Ex vivo motor-nerve recordings revealed sharper burst envelopes and reduced temporal dispersion after training, explained by a selective narrowing of slow, but not fast, motor neuron discharge within each cycle. Training enhanced phase-locked commissural inhibition during locomotion, consistent with an inhibitory gate aligned to burst offset. Finally, electrophysiology and single-cell transcriptomics associated this plasticity with increased glycinergic receptor expression in slow motor neurons. Together, our findings identify a circuit and a molecular substrate for training-induced gains in agility and suggest that motor precision can be improved by inhibitory reformatting of slow motor output rather than by uniformly increasing excitation.
Adolescence is characterized by heightened reward sensitivity and risky decision-making. Prevailing neurodevelopmental frameworks typically attribute these behavioral trends to a maturational imbalance between rapidly developing motivational brain regions, and slower-maturing prefrontal cognitive control circuitry. However, these models largely overlook the cerebellum-a structure that demonstrates protracted development across adolescence and reciprocal connectivity with both striatum and prefrontal cortex. Computational models also highlight the cerebellum's central role in reinforcement learning and error-based model updating, making it a potentially critical region for understanding adolescent reward processing. To evaluate this, we conducted a systematic literature search and coordinate-based meta-analysis of functional magnetic resonance imaging (fMRI) studies examining reward anticipation and receipt in healthy adolescents (19 studies; 55 cerebellar peaks). Results demonstrate a striking functional dissociation. During reward anticipation, adolescent cerebellar activation mirrors adult topographies-demonstrating widely distributed activation patterns across the cerebellar lobules and Vermis, localized to cerebellar regions that are functionally connected with salience, somatomotor, and frontoparietal cortico-cerebellar networks. Conversely, while reward receipt also elicits widespread cerebellar activation in adolescents, this stands in contrast to highly focal feedback-locked reward activity seen only in the Vermis in adult studies. We interpret these findings through the lens of cerebellar reinforcement learning. We argue that widespread reward outcome-locked BOLD activity in adolescents may reflect broader parallel fiber recruitment, supporting the active maintenance of short-timescale eligibility traces required for credit assignment while internal forward models are being constructed during development. Ultimately-rather than a biological epiphenomenon-it is hypothesized that this active cerebellar computation during adolescence may contribute to the developmental shaping of prefrontal networks necessary for normative regulation of motivation and decision-making in adulthood.
The use of natural fibers in concrete is a sustainable strategy to improve ductility and crack resistance; however, coconut fiber can introduce nonlinear interactions among mix constituents that complicate compressive strength prediction. This study proposes an optimized and explainable machine learning framework for compressive strength prediction of coconut fiber reinforced concrete (CFRC). Six regression algorithms, support vector machine (SVM), k-nearest neighbors (KNN), random forest (RF), light gradient boosting (LGB), extreme gradient boosting (XGB), and artificial neural network (ANN) were optimized using particle swarm optimization (PSO) on 586 experimental samples with eight inputs: cement, fine aggregate (FA), natural coarse aggregate (NCA), recycled coarse aggregate (RCA), water, fiber content, fiber length, and age. A nested grouped cross-validation scheme (outer 5-fold, inner 3-fold) was adopted for robust model selection, followed by evaluation on a locked 30% test set. The best model, XGB-PSO, achieved mean cross-validation performance of R2 = 0.963 ± 0.013, RMSE = 3.018 ± 0.646 MPa, MAPE = 7.744 ± 1.008% and demonstrated strong generalization on the locked test set (R2 = 0.953, RMSE = 3.71 MPa, MAPE = 8.875%). Model explainability using shapley additive explanations (SHAP), partial dependence plots (PDP), accumulated local effects (ALE), and individual conditional expectation (ICE) consistently identified age and RCA as dominant predictors, supporting data driven CFRC mix design and optimization.
Many Clostridioides difficile strains can form two colony morphotypes: rough and smooth. The rough and smooth morphotypes differ in multiple phenotypes, including cell length and chaining, motility, biofilm production, and virulence in the hamster model of C. difficile infection (CDI). Colony morphology undergoes phase variation and is determined by the ON/OFF expression of cmrRST, which encodes a signal transduction system. Here, we test the hypothesis that differences in colony morphology and the associated phenotypes influence pathogenesis and the host response to infection. We first compared the rough and smooth colony variants of wild-type C. difficile in a mouse model of CDI. However, CmrRST phase varied during infection such that the C. difficile populations became indistinguishable in feces and tissues, and no differences in disease were observed in mice inoculated with these variants. We next circumvented phase variation using mutants that form only rough or only smooth colonies. Co-infection of mice with these phenotypically locked strains revealed that the smooth colony mutant has greater fitness than the rough mutant, which is outcompeted during late infection. In addition, NanoString analyses showed a higher number of differentially expressed pro-inflammatory genes and overall higher expression levels in mice infected with the rough colony mutant, independent of bacterial burden and toxin levels. Our results indicate that in a mouse model of CDI, cells from rough colonies are more immunostimulatory during early murine infection, potentially leading to reduced relative fitness compared to cells from smooth colonies.
Action prediction is critical for success in fast, interactive sports and depends on integrating contextual priors with moment-to-moment kinematic evidence. However, how these information sources are dynamically weighted under varying information availability remains insufficiently understood. We addressed this question in a table tennis action prediction task by manipulating kinematic information availability (high vs. low) and contextual prior (congruent, incongruent, absent) while recording electroencephalography (EEG) in athletes and non-athletes. Thirty-two table tennis athletes and forty-two non-athletes observed serve clips and predicted the landing location. Behaviorally, athletes showed higher overall accuracy, and congruent priors facilitated performance whereas incongruent priors impaired it. Critically, athletes were less susceptible to misleading priors, particularly when more kinematic information was available, consistent with reliability-based reweighting toward sensory evidence. Cue-locked ERPs revealed reduced P3 amplitudes in athletes, suggesting more efficient processing of prior cues and contextual updating. During kinematic processing, athletes exhibited stronger mu (8-13Hz) desynchronization and a context-sensitive modulation pattern, mu suppression increased in congruent/high-information trials but was relatively enhanced in low-information trials when priors were incongruent or absent, reflecting adaptive scaling of sensorimotor engagement under uncertainty. Non-athletes showed weaker selectivity. Together, these findings provide time-resolved behavioral and EEG observations compatible with accounts of action prediction that emphasize reliability-weighted integration of prior and kinematic information, and suggest that motor expertise may be associated with greater flexibility in this process.
This study evaluated the effectiveness of a brief, Theory of Planned Behavior-based educational program on weight management and related health outcomes among university employees. In this quasi-experimental study conducted at two major universities in Erbil, Iraq, 200 employees with a body mass index (BMI) ≥ 25 kg/m² self-selected into an intervention (n = 100) or control (n = 100) group. The intervention consisted of five individual 35-40-minute sessions delivered over 12 weeks and covered obesity awareness, culturally adapted nutrition education, physical activity, and behavior-change strategies. The control group received only standard written materials. Primary outcomes were changes in body weight, BMI, and waist circumference. Secondary outcomes included lipid profile, fasting glucose, quality of life (Impact of Weight on Quality of Life-Lite [IWQOL-Lite]), dietary quality, and physical activity. All assessments were performed at baseline and 12 weeks. The intervention was associated with a mean weight loss of 7.46 kg (95% CI 6.44-8.48) compared with a gain of 0.58 kg in the control group (adjusted difference - 8.04 kg; p < 0.001; Cohen's d = 2.40). 79% of intervention participants lost ≥ 5% of their initial body weight (versus 0% in controls), and 41% lost ≥ 10%. Significant improvements were also observed in BMI, waist circumference, lipid profile, quality of life, and dietary quality (all p < 0.001; d > 1.8). Mediation analysis indicated that improvement in dietary quality accounted for 82% of the observed association between group assignment and change in BMI. A brief, low-cost, culturally adapted educational intervention delivered in the workplace was associated with exceptionally large weight loss, cardiometabolic benefits, and psychosocial gains, with perfect retention. These findings suggest that this model may offer a promising approach for obesity management in Middle Eastern settings. However, confirmation in randomized controlled trials with longer follow-up is required before firm conclusions regarding scalability and effectiveness can be drawn. The study was not prospectively registered in a clinical trial registry because it employed a quasi-experimental design with participant self-selection rather than random allocation. However, the full study protocol including all primary and secondary outcomes, eligibility criteria, intervention details, and the statistical analysis plan was finalized, approved by the Hawler Medical University Ethics Committee (reference HMU-REC-2024-18, 15 September 2024), and locked prior to the start of participant recruitment and data collection. No outcomes were added, removed, or modified after data inspection, and no post-hoc analyses were conducted beyond those pre-specified in the protocol. The manuscript adheres fully to the TREND reporting standards for non-randomized evaluations.
Acetylene (C2H2) is an essential chemical feedstock, yet removing carbon dioxide (CO2) impurities in a single step remains a formidable challenge due to their nearly identical molecular sizes and boiling points. Here, we present that by releasing a "narrow-channel lock" through functional-group modulation, a porous crystal (NTU-87) overcomes this limitation. The parent framework NTU-87-NH2 contains isolated nanopockets locked by -NH2 groups, exhibiting negligible adsorption difference between CO2 and C2H2 (2.9 cm3 g-1 at 0.5 bar, 298 K). Removing these groups transforms the structure into NTU-87 with a ball-neck channel, markedly reversing the adsorption preference and amplifying the difference to 15.6 cm3 g-1. Breakthrough experiments confirm that NTU-87 binds CO2 more strongly than C2H2, enabling single-step production of pure C2H2 from CO2/C2H2 mixtures with low regeneration energy. This strategy of unlocking confined pore architectures establishes functional-group regulation as a general route to high-performance gas purification.
Perioperative ischemic stroke is uncommon overall but frequent in cardiac, major vascular, and neurosurgical procedures. Existing calculators often exclude these settings and rarely incorporate cerebrovascular disease markers available in routine electronic health record data. We assembled a retrospective cohort of adults undergoing procedures at 3 hospitals (January 2016-June 2024). The model was derived at Rhode Island Hospital (255 850 procedures) and externally validated at 2 affiliated hospitals (The Miriam Hospital/Newport Hospital; 189 095 procedures). Candidate predictors included age, vascular comorbidities, documented carotid stenosis and intracranial atherosclerosis, procedure setting (ambulatory versus inpatient/emergency), and procedural service (including vascular versus nonvascular neurosurgery and open versus interventional cardiovascular procedures). We fit a multivariable logistic regression model with internal validation using 1000 bootstrap resamples and assessed calibration by observed versus predicted risk across deciles. External validation applied locked derivation coefficients without refitting. Strokes occurred in 1235/255 850 derivation procedures (0.48%) and 418/189 095 validation procedures (0.22%). Independent predictors included older age, prior stroke or transient ischemic attack (adjusted odds ratio [aOR], 6.66), inpatient/emergency setting (aOR, 4.25 versus ambulatory), vascular neurosurgery (aOR, 6.70 versus general surgery), and open cardiovascular procedures (aOR, 4.14). Discrimination was high (derivation area under the curve, 0.87 [95% CI, 0.87-0.88]; optimism-corrected area under the curve, 0.87; validation area under the curve, 0.86 [95% CI, 0.84-0.87]) with good calibration. Prespecified risk strata (<1%, 1-5%, >5%) separated observed event rates in both cohorts. A pragmatic, electronic health record-derived model integrating procedural category and cerebrovascular disease accurately predicts 30-day periprocedural ischemic stroke across diverse procedures and is available as a web-based calculator to support counseling and targeted prevention.
Nuclear Factor-kappa B (NF-κB) is a master transcriptional regulator orchestrating critical cellular processes, predominantly immunity and inflammation. However, its aberrant constitutive activation has emerged as a unifying pathogenetic hallmark across diverse malignancies, autoimmune disorders, and chronic inflammatory diseases. While the fundamental biology of canonical and non-canonical NF-κB signalling is well-established, translating this extensive knowledge into clinically viable therapeutics remains severely hindered by dose-limiting systemic toxicities and complex pharmacokinetic liabilities. This review critically evaluates the transition of NF-κB from a basic biological paradigm to a highly challenging yet promising therapeutic target. After a streamlined synthesis of its signalling dynamics and pathological implications across various disease states, the core focus of this report shifts to an in-depth analysis of next-generation therapeutic interventions. We specifically dissect advanced molecular strategies, moving beyond conventional pharmacological inhibitors to emphasize nucleic acid-based therapies, including decoy oligodeoxynucleotides (ODNs), peptide nucleic acids (PNAs), and locked nucleic acids (LNAs). Furthermore, we critically address current translational bottlenecks, highlighting the pivotal role of lipid nanoparticle (LNP) transporters and smart drug delivery systems in overcoming off-target effects. By mapping these cutting-edge modalities, this review underscores the critical necessity of transitioning from broad-spectrum inhibition toward context-specific, precision-engineered modulation of the NF-κB axis.
Long-term androgen deprivation therapy (LT-ADT) with radiotherapy is standard-of-care for high-risk localized prostate cancer, with abiraterone added for clinically very high-risk disease. Given the toxicity and cost of abiraterone, a predictive biomarker to refine patient selection is needed. We evaluated a digital pathology multimodal artificial intelligence (MMAI) model, previously validated as a prognostic biomarker, for prediction of abiraterone benefit amongst non-metastatic clinically very high-risk prostate cancer. MMAI scores were generated for patients enrolled in two sequential abiraterone trials (no shared controls) in the STAMPEDE platform protocol (NCT00268476) using digital pathology images, prostate specific antigen (PSA), tumor stage, and age. We applied the previously-established 75th percentile threshold to classify patients as MMAI very high-risk or standard high-risk. The primary endpoint was metastasis-free survival (MFS). Treatment effects and risk estimates were obtained using Cox regression and Kaplan-Meier method, respectively. Prediction was assessed using a treatment-by-biomarker interaction Cox model. In total, 1137 patients randomized to LT-ADT (N=583) or LT-ADT with abiraterone (N=554), were included. The MMAI very high-risk group (N=268) demonstrated significant MFS improvement from adding abiraterone (HR 0.47; 95% CI 0.31-0.70), with 5-year MFS increasing from 62% (95% CI 53-70%) in LT-ADT to 81% (95% CI 74-87%) in LT-ADT with abiraterone. Limited abiraterone benefit was observed in the MMAI standard high-risk group (N=869; HR 0.83; 95% CI 0.63-1.09), with a 5-year MFS of 82% (95% CI 78-85%) versus 84% (95% CI 80-87%, interaction p-value=0.02). This differential effect was consistent in local node-negative and node-positive subgroups. In this post-hoc study of randomized clinical trial data, a locked digital pathology MMAI test displayed a strong prognostic association and predicted abiraterone efficacy in very high-risk, non-metastatic prostate cancer. This biomarker could be implemented clinically to maximize benefit from treatment intensification whilst avoiding unnecessary toxicity.
During monotonous tasks, struggling with drowsiness leads to dynamic fluctuations in vigilance and task performance. Whether these moment-to-moment fluctuations are regulated by sleep-wake control circuitry remains unknown. Here, we used high-resolution 7T fMRI optimized for subcortical imaging to resolve activity across the human arousal regulatory system, including the hypothalamus, brainstem nuclei, basal forebrain, and thalamus, during a sustained attention task as subjects spontaneously experienced drowsiness. We identified a coordinated activity pattern locked to behavioral failures: widespread transient suppression during arousal drops and reactivation during recovery across all arousal-promoting regions, with opposite responses in the sleep-promoting hypothalamic preoptic area. These changes unfolded over ~10-15 s in a 30 consistent sequence, led by the hypothalamic nuclei. Furthermore, suppression of brainstem nuclei preceded cortical infraslow (<0.05 Hz) oscillations, implicating a role in global neurovascular dynamics. These findings provide a temporally resolved, network-level portrait of human subcortical dynamics during drowsiness and identify a hypothalamic-led, brainstem-mediated activity sequence underlying behavioral arousal fluctuations and global cortical hemodynamics.
Progressive cognitive decline and loss of white matter integrity are observed during aging, but whether these two processes are connected remains unclear. We propose the Decoherence via Demyelination Hypothesis (DDH) as a mechanism linking non-uniform, tract-specific myelin loss during aging, which results in the degradation of conduction timing that is required to coordinate long-range neuronal assemblies. This impairs the dynamic assembly of task-dependent functional networks and promotes age-associated cognitive change. Axonal myelination determines conduction velocity as well as signal transmission fidelity, properties essential for phase-locked integration of long-distance inputs with local oscillations and for the assembly of mesoscale functional brain networks. If myelin loss is heterogeneous across tracts, the resulting timing perturbations should be heterogeneous as well, with disproportionate impact on networks supporting higher-order cognition. To test this, we analyzed structural and microstructural MRI in 638 individuals aged 40-99, quantifying fasciculation in different white matter pathways as well as neurite orientation dispersion and density imaging (NODDI) to the gray-white matter interface beneath cortical regions. We observed tract-specific, non-uniform myelin decline, with significant nonlinear losses in tracts serving high order cognition and memory (uncinate fasciculus, fornix, corpus callosum), consistent with accelerated late-life vulnerability in pathways implicated in cognitive aging and increased risk for neurodegenerative diseases. Tract-level degeneration tracked with age-related shifts in network organization and cognition. These findings may support DDH as a framework for age-associated cognitive change. Particularly, tract-specific timing perturbations drive the breakdown of coordinated network activity in aging.
A trigger finger, also known as stenosing tenosynovitis, occurs when a digit becomes locked in a flexed position due to inflammation of the tendon sheath, restricting smooth tendon excursion. Pediatric trigger fingers (PTF) are less common and consequently less well-characterized - frequently classified as congenital - although the etiology remains heterogeneous and incompletely understood. In this case study, we explore the case of a three-year-old male with flexion deformities of bilateral long and ring fingers. The patient underwent two trigger finger surgeries; the first was a release of the A-1 pulleys, and the second involved a Bruner incision and the excision of the ulnar slip of the flexor digitorum superficialis tendon in all four digits. This case underscores the clinical and surgical complexity of PTF and the corresponding need for more nuanced workup and surgical procedure. Through this exploration, as well as through further investigation of previously published studies, we can appreciate PTF as heterogeneous mechanical disorders rather than a single strict definition.
Appendiceal neoplasms (ANs) may mimic acute appendicitis (AA), making preoperative recognition difficult in emergency settings. We aimed to derive and externally validate a simple non-contrast CT criterion combining appendiceal diameter and fecalith obstruction status for differentiating AN from AA. This multicenter retrospective case-control study included adults who underwent appendectomy at four tertiary hospitals from January 2013 to June 2025. Histopathology after centralized re-review served as the reference standard. In the derivation cohort, receiver operating characteristic analysis was used to determine the optimal cutoff for maximum appendiceal diameter. A locked criterion of significantly enlarged appendiceal diameter (SEAD) without fecalith obstruction was then applied unchanged to the validation cohorts and reader-based validation subsets. Its diagnostic performance was also compared with that of the original CT reports. The final analytic cohort included 292 patients with ANs and 876 controls with AA. A cutoff of 12.48 mm defined SEAD. In the derivation cohort, SEAD without fecalith obstruction yielded an AUC of 0.76 (95% CI, 0.71-0.80), with 64.1% sensitivity and 87.0% specificity. In Center 2, the AUC was 0.82 (95% CI, 0.77-0.87), and in the pooled Centers 3 and 4 cohort it was 0.73 (95% CI, 0.66-0.81), without significant differences versus the derivation cohort (p = 0.051 and p = 0.598). Reader-based AUCs were 0.80, 0.76, and 0.72, without significant between-reader differences (all p > 0.05). Compared with original CT reports, the criterion substantially improved preoperative AN detection across cohorts (all p < 0.001). A predefined non-contrast CT criterion of SEAD without fecalith obstruction may facilitate preoperative identification of AN in patients with presumed AA.
Epileptic seizures and interictal epileptiform discharges are strongly influenced by sleep and circadian rhythms. However, human data on the effect of sleep on neuronal behaviour during interictal activity have been lacking. We analysed EEG from eight epileptic patients implanted with macro and micro electrodes in mesial temporal structures. Sleep staging was performed on polysomnography and video-EEG. Automated detection identified thousands of interictal epileptiform discharges per patient. Both their rate and amplitude increased with deeper stages of non-rapid eye movement sleep. Single- and multi-unit firing rates were often temporally coupled with local field potentials, exhibiting increased firing during the spike and decreased activity during the following slow wave. These time-locked firing rate modulations were shown to increase during deeper stages of non-rapid eye movement sleep. Furthermore, neuronal background activity showed a decrease in firing rate, bursting and regularity with deeper stages of non-rapid eye movement sleep.
Bacteria precisely regulate the place and timing of their cell division. One of the best-understood systems for division site selection is the Min system in Escherichia coli. In E. coli, the Min system displays remarkable pole-to-pole oscillation, creating a time-averaged minimum at the cell's geometric center, which marks the future division site. Interestingly, the Gram-positive model species Bacillus subtilis also encodes homologous proteins: the cell division inhibitor MinC and the Walker-ATPase MinD. However, B. subtilis lacks the activating protein MinE, which is essential for Min dynamics in E. coli. We have shown before that the B. subtilis Min system is highly dynamic and quickly relocalizes to active sites of division. This raised questions about how Min protein dynamics are regulated on a molecular level in B. subtilis. Here, we show with a combination of in vitro experiments and in vivo single-molecule imaging that the ATPase activity of B. subtilis MinD is activated by membrane binding. Additionally, both monomeric and dimeric MinD bind to the membrane, and binding of ATP to MinD is a prerequisite for fast membrane detachment. Single-molecule localization microscopy data confirm membrane binding of monomeric MinD variants. However, only wild-type MinD enriches at cell poles and sites of ongoing division, likely due to interaction with MinJ. Monomeric MinD variants and locked dimers remain distributed along the membrane and lack the characteristic pattern formation. Single-molecule tracking data further support that MinD has a freely diffusive population, which is increased in the monomeric variants and a membrane-binding defective mutant. Thus, MinD dynamics in B. subtilis under the tested conditions do not require any unknown protein component and can be fully explained by MinD's binding and unbinding kinetics with the membrane. The spatial organization of MinD relies on the short-lived temporal residence of MinD dimers at the membrane.
Displaced femoral neck fractures in physiologically young patients remain a significant treatment challenge due to high complication rates associated with internal fixation, including osteonecrosis, non-union, and hardware failure. This case report describes the successful use of a novel implant, the SimpliFix Hip System, in the surgical management of a 30-year-old female marathon runner who sustained a displaced transcervical femoral neck fracture. Following closed reduction on a fracture table, three partially threaded cannulated screws were inserted and cross-locked with headless cross screws using the SimpliFix system, which permits controlled compression and rotational stability while minimizing implant footprint. The construct was configured to impart rigidity at the calcar and controlled valgus compression to promote union. Postoperatively, the patient was maintained toe-touch weightbearing for 10 weeks. Radiographs at routine follow-up demonstrated anatomic healing without evidence of implant failure or loss of reduction. At one year, the patient had resumed pre-injury activity levels, running 50 miles per week without pain or limitation. This case demonstrates the potential advantages of the SimpliFix system in young, active patients, particularly its capacity to resist femoral neck shortening, maintain reduction, and enhance biomechanical stability while preserving minimally invasive technique. The positive clinical and radiographic outcome highlights the promise of this implant as an alternative to conventional compression screws or fixed-angle devices. Further studies are warranted to assess long-term outcomes and comparative efficacy.
Renewable energy resources (RESs) are typically integrated into the utility grid through grid-connected inverters (GCIs). Such a system may lose synchronization during grid faults, especially under weak grid conditions, resulting in instability problems or even triggering large-scale power outage accidents. This paper analyzes the influences of the system parameters, including the phase-locked loop (PLL) parameters and the grid parameters, on the GCI's synchronous stability. The results reveal that the PLL exhibits a negative damping effect during the transient process, which is bad for stabilizing the GCI in transients. An improved PLL, which is achieved by adding a feedback low-pass filter into the conventional PLL, is then proposed to address this issue, making the system more stable in transients. Analyzing results show that the improved PLL can enhance the synchronous stability of GCI during transients without changing its steady-state performance. The simulation and experimental results performed by a 2-MW GCI integrated into a weak grid verify the correctness of the theoretical analysis and the effectiveness of the proposed method.