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Precoding is a critical signal processing technique used in wireless communication systems to enhance transmission performance. This paper initially provides a brief overview of various conventional precoding algorithms. The exploration includes various nonlinear precoding algorithms which outperform linear techniques in high signal-to-noise ratio (SNR) scenarios. Moreover, the paper delves into practical considerations and provides insights into selecting the most suitable technique for specific communication scenarios. The deep learning-based hybrid precoder is designed using the MDL-AltMin algorithm and simulated results show a spectral efficiency of (SE) 40.96 dB compared with different precoding algorithms. The precoder model is modified with a Hybrid Precoding Net algorithm with a spectral efficiency of 21.07 dB for high values of SNR such as −30 and again compared with deep learning precoders. The HPNet model is proposed with a spectral efficiency of 23.04 dB with and without CSI (Channel State Information) at the transmitter. Furthermore, the HPNet model is compared with optimal digital precoders.

La infertilidad afecta aproximadamente al 15%-20% de las parejas, con factores tanto femeninos como masculinos y mixtos, así como causas idiopáticas o desconocidas. Las principales causas de infertilidad femenina incluyen disfunciones ovulatorias, anomalías uterinas o cervicales, problemas en las trompas de Falopio y causas endocrinológicas como: síndrome de ovario poliquístico, hiperprolactinemia, hipotiroidismo, hipertiroidismo y obesidad. La evaluación comienza con una historia médica completa y un examen físico, seguidos de pruebas para evaluar la función ovulatoria y análisis bioquímicos y hormonales. Por su parte, la infertilidad masculina, que afecta a una parte significativa de las parejas, puede ser causada por: disfunción testicular, endocrinopatías, factores del estilo de vida, anomalías anatómicas congénitas, exposiciones a gonadotóxicos y envejecimiento. La evaluación incluye una historia médica detallada y un examen físico completo, seguido de análisis de semen para evaluar la concentración, motilidad y morfología espermática. También se realizan pruebas de imagen y estudios moleculares y cromosómicos en casos específicos.

Sand control is an ongoing challenge in numerous hydrocarbon-producing wells in sand-rich reservoirs. Sand production in these wells can cause damage to equipment, reduce production rates, and lead to erosion that can damage subsea equipment, production equipment, well completions, and surface facilities. This problem can compromise the mechanical integrity of the well, resulting in reduced hydrocarbon production and increased operating expenses. This review evaluates various sand production mechanisms, including geological and mechanical production methodologies, and fluid-related aspects, which are thoroughly investigated to offer a thorough understanding of the complexity of the issue and the state of sand prediction approaches. Empirical correlations, numerical simulations, and analytical models are among the sand production prediction techniques critically assessed in this study. The benefits, drawbacks, and suitability of these techniques for various reservoir environments are discussed. Furthermore, the potential benefits of combining Fiber optic (FO) technologies and machine learning (ML) for real-time monitoring and mitigation are highlighted. This integrated strategy has the potential to transform sand control practices of the industry, as demonstrated by case studies and new research that highlights its effectiveness. The future vision outlined in this review includes developments in automation, data processing methods, and sensor technologies, which should improve the precision and dependability of sand production predictions and mitigation. In conclusion, this review paper provides an extensive analysis of the current level of prediction techniques, as well as the mechanisms behind sand production in oil and gas wells. This highlights how real-time, data-driven solutions for monitoring and addressing sand production problems may be provided by FO and ML, which can ultimately lead to safer and more effective hydrocarbon recovery operations.

IMPORTANCE: There are reported benefits from vitrectomy for diabetic macular edema (DME); however, data precede anti–vascular endothelial growth therapy (VEGF) therapy, supporting a need to assess the current role of vitrectomy. OBJECTIVE: To determine rates of recruitment and efficacy outcomes of vitrectomy plus internal limiting membrane (ILM) peeling adjunctive to treat-and-extend (T&E) anti-VEGF injections for diabetic macular edema (DME). DESIGN, SETTING, AND PARTICIPANTS: This was a single-masked, multicenter randomized clinical trial at 21 sites in the United Kingdom from June 2018 to January 2021, evaluating single eyes of treatment-naive patients with symptomatic vision loss from DME for less than 1 year. Inclusion criteria were best-corrected visual acuity (BCVA) Early Treatment Diabetic Retinopathy Study letter score greater than 35 (approximate Snellen equivalent, 20/200 or better) and central subfield thickness (CST) greater than 350 μm after 3 monthly intravitreal injections of ranibizumab or aflibercept. Data analysis was performed in July 2023. INTERVENTIONS: Patients were randomized 1:1 into vitrectomy plus standard care or standard care alone and further stratified into groups with vs without vitreomacular interface abnormality. Both groups received a T&E anti-VEGF injection regimen with aflibercept, 2 mg, or ranibizumab, 0.5 mg. The vitrectomy group additionally underwent pars plana vitrectomy with epiretinal membrane or ILM peel within 1 month of randomization. MAIN OUTCOMES AND MEASURES: Rate of recruitment and distance BCVA. Secondary outcome measures were CST, change in BCVA and CST, number of injections, rate of completed follow-up, and withdrawal rate. RESULTS: Over 32 months, 47 of a planned 100 patients were enrolled; 42 (89%; mean [SD] age, 63 [11] years; 26 [62%] male) completed 12-month follow-up visits. Baseline characteristics appeared comparable between the control (n = 23; mean [SD] age, 66 [10] years) and vitrectomy (n = 24; mean [SD] age, 62 [12] years) groups. No difference in 12-month BCVA was noted between groups, with a 12-month median (IQR) BCVA letter score of 73 (65-77) letters (Snellen equivalent, 20/40) in the control group vs 77 (67-81) letters (Snellen equivalent, 20/32) in the vitrectomy group (difference, 4 letters; 95% CI, −8 to 2; P = .24). There was no difference in BCVA change from baseline (median [IQR], −1 [−3 to 2] letters for the control group vs −2 [−8 to 2] letters for the vitrectomy group; difference, 1 letter; 95% CI, −5 to 7; P = .85). No difference was found in CST changes (median [IQR], −94 [−122 to 9] μm for the control group vs −32 [−48 to 25] μm for the vitrectomy group; difference, 62 μm; 95% CI, −110 to 11; P = .11). CONCLUSIONS AND RELEVANCE: Enrollment goals could not be attained. However, with 47 participants, evidence did not support a clinical benefit of vitrectomy plus ILM peeling as an adjunct to a T&E regimen of anti-VEGF therapy for DME. TRIAL REGISTRATION: isrctn.org Identifier: ISRCTN59902040

The distribution pattern of a taxon is a consequence of historical and contemporary processes—specifically ecological and evolutionary processes—which tend to result in distributional congruence among species that respond similarly to the same processes. This congruence leads to the establishment of areas of endemism that are important for delimiting biogeographic regions. In the Neotropical region, different definitions of area of endemism have been proposed based on the distributional patterns of mammal species, each according to different methods and assumptions. In this study, we aimed to identify areas of endemism of Neotropical mammals, represented by 361 species of Placentalia (Xenarthra, Chiroptera, and Carnivora) and Marsupialia (Didelphimorphia and Paucituberculata), using an endemicity analysis implemented by the software NDM (eNDeMism software) and a hierarchical cluster analysis based on Simpson’s beta dissimilarity metric (βsim). The results suggest alternative spatial configurations within northern and southern parts of the Neotropics along transition zones. Additionally, there are indications of more restricted areas of endemism throughout the Neotropical region and with more species supporting the areas, such 1 area located in the region corresponding to the Atlantic forest and 2 areas corresponding to Mexican transition zone. The study enhances our understanding of Neotropical mammal biogeography and underscores the importance of using primary distribution data. Previous studies found 82 endemic species based on range maps, whereas our analyses identified 172 endemic species, including 125 that are newly proposed as such, and also confirmed the existence of 47 previously reported endemic species.In this study, we identified areas of endemism for Neotropical mammals, represented by 361 species of placental and marsupial mammals based on endemicity analysis. Our results show that the Neotropical region is composed of 24 groups of endemic areas, supported by 172 endemic species. Although the present study does not have the objective of proposing a new regionalization scheme, the convergent patterns recovered by 2 analytical approaches suggest that attention to further defining the limits of the Neotropical region is needed.

Although previous studies have demonstrated the efficacy of faricimab in treatment-naive patients with neovascular age-related macular degeneration (nAMD), its outcomes in patients switched from aflibercept are less understood. This study aimed to assess clinical anatomical and functional outcomes of switching to faricimab in patients undergoing aflibercept intravitreal injections (IVIs) for nAMD with suboptimal response.

This study delves into the intricate relationship between Absorptive Capacity, Organizational Learning, and the Learning Organization. It introduces Absorptive Capacity 4.0, a dynamic framework that traces an organization's evolution towards a comprehensive Learning Organization by redefining absorptive capacity to include value realization, multi-layered learning processes, and strategic adaptability. Emphasizing continuous adaptation, the research demonstrates how firms excel by adjusting their learning strategies to embrace technological advancements and market dynamics. Through empirical analysis and reconceptualization, it highlights the importance of a robust absorptive capacity framework for organizational competence, sustainable innovation, and competitive advantage. The study concludes a practical exploration using a case study of an SME, aligning its strategic adaptability with the Absorptive Capacity 4.0 model, It also suggests implications for future research and advocating for a shift towards a learning-centric organizational culture in various industries.

Background: Hip surgery is often necessary for children with severe neuromuscular disabilities to avoid chronic pain resulting from hip migration. This study correlated the Surgical Vulnerability Score (SVS), a novel measure of physiological reserve, with reconstructive hip surgery outcomes to improve shared surgical decision-making. Materials and methods: Sixty-eight cases performed by a single surgeon were retrospectively evaluated. Cases were graded according to physiological vulnerability using the SVS, which was then correlated with two outcomes: length of hospital stay (LOS) and severity of postoperative complications. The Gross Motor Function Classification System (GMFCS) level was used as a baseline comparison. Sub-analysis compared results for patients who underwent only a femoral varus derotation osteotomy (VDRO) (n= 48) with those who underwent a combined VDRO and Dega Pelvic Osteotomy (Dega PO) (n= 20). Results: Results showed that a higher SVS was associated with increased LOS (p = 0.001) and severity of postoperative complications (p= 0.0008). A greater GMFCS level was not associated with either LOS (p= 0.246) or the severity of postoperative complications (p= 0.282). For patients who underwent only a VDRO, an increase in SVS had no association with LOS (p= 0.483) or severity of complications (p= 0.981). However, for patients who underwent both a VDRO and Dega PO, a higher SVS was associated with increased LOS (p= 0.0002) and severity of complications (p= 0.0001). Conclusions: The SVS can aid surgical decision-making and prepare the child’s family for surgery. Early intervention and fixation using only a VDRO may lead to better outcomes, underscoring the importance of hip surveillance programs in the early identification of migrating hips.

Purpose: Surgical robotics have demonstrated their significance in assisting physicians during minimally invasive surgery. Especially, the integration of haptic and tactile feedback technologies can enhance the surgeon’s performance and overall patient outcomes. However, the current state-of-the-art lacks such interaction feedback opportunities, especially in robotic-assisted interventional magnetic resonance imaging (iMRI), which is gaining importance in clinical practice, specifically for percutaneous needle punctures. Methods: The cable-driven ‘Micropositioning Robotics for Image-Guided Surgery’ (µRIGS) system utilized the back-electromotive force effect of the stepper motor load to measure cable tensile forces without external sensors, employing the TMC5160 motor driver. The aim was to generate a sensorless haptic feedback (SHF) for remote needle advancement, incorporating collision detection and homing capabilities for internal automation processes. Three different phantoms capable of mimicking soft tissue were used to evaluate the difference in force feedback between manual needle puncture and the SHF, both technically and in terms of user experience. Results: The SHF achieved a sampling rate of 800 Hz and a mean force resolution of 0.26 ± 0.22 N, primarily dependent on motor current and rotation speed, with a mean maximum force of 15 N. In most cases, the SHF data aligned with the intended phantom-related force progression. The evaluation of the user study demonstrated no significant differences between the SHF technology and manual puncturing. Conclusion: The presented SHF of the µRIGS system introduced a novel MR-compatible technique to bridge the gap between medical robotics and interaction during real-time needle-based interventions.

Purpose: In vivo studies are often required to prove the functionality and safety of medical devices. Clinical trials are costly and complex, adding to ethical scrutiny of animal testing. Anthropomorphic phantoms with versatile functionalities can overcome these issues with regard to medical education or an effective development of assistance systems during image-guided interventions (e.g., robotics, navigation/registration algorithms). In this work, an MRI-compatible and customizable motion phantom is presented to mimic respiratory-triggered organ movement as well as human anatomy. Methods: For this purpose, polyvinyl alcohol cryogel (PVA-C) was the foundation for muscles, liver, kidneys, tumors, and remaining abdominal tissue in different sizes of the abdominal phantom body (APB) with the ability to mimic human tissue in various properties. In addition, a semi-flexible rib cage was 3D-printed. The motion unit (MU) with an electromagnetically shielded stepper motor and mechanical extensions simulated a respiration pattern to move the APB. Results: Each compartment of the APB complied the relaxation times, dielectricity, and elasticity of human tissue. It showed resistance against mold and provided a resealable behavior after needle punctures. During long-term storage, the APB had a weight loss of 2.3%, followed by changes to relaxation times of 9.3% and elasticity up to 79%. The MU was able to physiologically appropriately mimic the organ displacement without reducing the MRI quality. Conclusion: This work presents a novel modularizable and low-cost PVA-C based APB to mimic fundamental organ motion. Beside a further organ motion analysis, an optimization of APB’s chemical composition is needed to ensure a realistic motion simulation and reproducible long-term use. This phantom enhances diverse and varied training environments for prospective physicians as well as effective R&D of medical devices with the possibility to reduce in vivo experiments.

Introduction: Respiratory syncytial virus (RSV) burden in adults is underestimated mainly due to unspecific symptoms and limited standard-of-care testing. We estimated the population-based incidence of hospitalization and mortality attributable to RSV among adults with and without risk factors in Germany. Methods: Weekly counts of hospitalizations and deaths for respiratory, cardiovascular, and cardiorespiratory diseases were obtained (Statutory Health Insurance database, 2015–2019). A quasi-Poisson regression model was fitted to estimate the number of hospitalizations and deaths attributable to RSV as a function of periodic and aperiodic time trends, and viral activity while allowing for potential overdispersion. Weekly counts of RSV and influenza hospitalizations in children < 2 years and adults ≥ 60 years, respectively, were used as viral activity indicators. Models were stratified by age group and risk status (defined as presence of selected comorbidities). Results: Population-based RSV-attributable hospitalization incidence rates were high among adults ≥ 60 years: respiratory hospitalizations (236–363 per 100,000 person-years) and cardiorespiratory hospitalizations (584–912 per 100,000 person-years). RSV accounted for 2–3% of all cardiorespiratory hospitalizations in this age group. The increase in cardiorespiratory hospitalization risk associated with underlying risk factors was greater in 18–44 year old persons (five to sixfold higher) than in ≥ 75 year old persons (two to threefold higher). Conclusions: This is a first model-based study to comprehensively assess adult RSV burden in Germany. Estimated cardiorespiratory RSV hospitalization rates increased with age and were substantially higher in people with risk factors compared to those without risk factors. Our study indicates that RSV, like other respiratory viruses, contributes to both respiratory and cardiovascular hospitalizations. Effective prevention strategies are needed, especially among older adults ≥ 60 years and among adults with underlying risk factors.

With advances in our understanding regarding the neurochemical underpinnings of neurological and psychiatric diseases, there is an increased demand for advanced computational methods for neurochemical analysis. Despite having a variety of techniques for measuring tonic extracellular concentrations of neurotransmitters, including voltammetry, enzyme-based sensors, amperometry, and in vivo microdialysis, there is currently no means to resolve concentrations of structurally similar neurotransmitters from mixtures in the in vivo environment with high spatiotemporal resolution and limited tissue damage. Since a variety of research and clinical investigations involve brain regions containing electrochemically similar monoamines, such as dopamine and norepinephrine, developing a model to resolve the respective contributions of these neurotransmitters is of vital importance. Here we have developed a deep learning network, DiscrimNet, a convolutional autoencoder capable of accurately predicting individual tonic concentrations of dopamine, norepinephrine, and serotonin from both in vitro mixtures and the in vivo environment in anesthetized rats, measured using voltammetry. The architecture of DiscrimNet is described, and its ability to accurately predict in vitro and unseen in vivo concentrations is shown to vastly outperform a variety of shallow learning algorithms previously used for neurotransmitter discrimination. DiscrimNet is shown to generalize well to data captured from electrodes unseen during model training, eliminating the need to retrain the model for each new electrode. DiscrimNet is also shown to accurately predict the expected changes in dopamine and serotonin after cocaine and oxycodone administration in anesthetized rats in vivo. DiscrimNet therefore offers an exciting new method for real-time resolution of in vivo voltammetric signals into component neurotransmitters.

We established confrontations between two different fungi, i.e., the maize anthracnose and stalk rot pathogen Colletotrichum graminicola, and the ubiquitous fungus Aspergillus nidulans, and different biocontrol species, i.e., Bacillus subtilis, Bacillus velezensis, and Bacillus amyloliquefaciens. In all fungus–bacterium confrontations tested, growth arrest and, thus, distance inhibition was observed on solid substrata. LC–MS/MS analyses of culture filtrates suggested formation of several metabolites only synthesized in confrontations. Interestingly, microscopy of fungal hyphae grown in liquid medium showed protrusions and color changes occurred only in media harboring fungus-bacterium confrontations. These observations indicate metabolic re-programming and suggest formation of putative secondary metabolites in interactions involving microbial biocontrol agents.

The comparative understanding between cellular basis of transmission and clinical severities caused by Wuhan, Delta and Omicron strains of SARS-CoV-2 is important. To conduct In-Vitrostudies on cellular infection caused by different variants by performing cytotoxic assays and studying the live microscopic observations. The swab samples positive for Wuhan, Delta and Omicron strains were inoculated in the Vero cell lines and their rate of infectivity and nature of cytopathy was observed. The study showed maximum inter cellular connectivity among cells infected by Delta variant, followed by Wuhan and least inter cellular connections in the cells infected by Omicron variant. The Delta strain causing highest mortality as per reported epidemiological trends, showed highest inter cellular connections and maximum cell damage supporting the fastest cell to cell spread of infection and causing most mortality among patients. The paper reports that numerous inter cellular connections is the cause of spread of infection among cells and maximum cell damage as the cause of clinical severities. The paper sensitizes the issue that 52 subunit of viral Spike Protein could act as fusion enzyme causing the numerous inter cellular connections. Study suggests that the S2 subunit of the viral Spike Protein could be the drug target for therapeutic intervention.

ObjectiveTo study seizures in patients hospitalised due to SARS-CoV-2 infection, and compare their severity with seizures in patients hospitalised due to other viral respiratory tract infections (RTIs).DesignObservational population-based cohort study.SettingNorthern Stockholm.PatientsPatients aged 1 month–18 years hospitalised due to SARS-CoV-2 with and without seizures, and patients of the same age hospitalised due to other viral RTIs with seizures, between 1 March 2020 and 30 June 2022.Main outcome measuresThe prevalence of seizures in hospitalised patients due to SARS-CoV-2, the evaluation of assumed predictors of seizures and the comparison of severity markers in patients with SARS-CoV-2 versus other RTIs.Results32 of 239 included patients (13.4%) admitted due to SARS-CoV-2 infection had seizures. Central nervous system (CNS) disease and the omicron period had significantly increased OR for seizures (OR: 5.12; CI: 2.06 to 12.72 and OR: 3.01; CI: 1.15 to 7.88, respectively). Seizures in patients with SARS-CoV-2 were more common in children older than 5 years (p=0.001), even in the absence of fever (p=0.007), as compared with other viral RTIs. The duration of hospitalisation was longer in patients with seizures due to other viral RTIs (p=0.023). There was no significant difference regarding severity markers of seizures between the two groups.ConclusionsCNS disease and the omicron period were risk factors for seizures in patients with SARS-CoV-2, who were older than patients with other RTIs. The severity of seizures was comparable between the two groups; hospitalisation was however longer in patients with other RTIs.

AimsThe purpose of this study is to evaluate the accuracy and validity of the determination of cause of death (COD) and manner of death (MOD) at the completion of the forensic autopsy prosection.MethodsWe analysed 952 autopsy cases conducted from 2019 to 2020 and compared every patient’s COD, other significant contributing factors to death (OSC), and MOD after prosection to their COD, OSC and MOD after completion of the final autopsy report.ResultsWe found that 83% of cases (790 patients) did not have an unexpected change and 17% of cases (162 patients) exhibited a true change in their final diagnosis; the relationship between age and changes in COD and MOD was significant.ConclusionsOur findings indicate that in the majority of forensic autopsy cases, medical professionals can reasonably complete death certification after the autopsy prosection. In addition to improving the accuracy of COD and MOD, advances in this field will enhance timely decedent affairs management, timely investigations of crimes and timely closure to families who have lost loved ones. We recommend implementing combined interventional education and consultation with expert pathologists, and a well-followed structured method of death classification as the best course of practice.

Nanophotonic devices manipulate light at sub-wavelength scales, enabling tasks such as light concentration, routing, and filtering. Designing these devices to achieve precise light–matter interactions using structural parameters and materials is a challenging task. Traditionally, solving this problem has relied on computationally expensive, iterative methods. In recent years, deep learning techniques have emerged as promising tools for tackling the inverse design of nanophotonic devices. While several review articles have provided an overview of the progress in this rapidly evolving field, there is a need for a comprehensive tutorial that specifically targets newcomers without prior experience in deep learning. Our goal is to address this gap and provide practical guidance for applying deep learning to individual scientific problems. We introduce the fundamental concepts of deep learning and critically discuss the potential benefits it offers for various inverse design problems in nanophotonics. We present a suggested workflow and detailed, practical design guidelines to help newcomers navigate the challenges they may encounter. By following our guide, newcomers can avoid frustrating roadblocks commonly experienced when venturing into deep learning for the first time. In a second part, we explore different iterative and direct deep learning-based techniques for inverse design, and evaluate their respective advantages and limitations. To enhance understanding and facilitate implementation, we supplement the manuscript with detailed Python notebook examples, illustrating each step of the discussed processes. While our tutorial primarily focuses on researchers in (nano-)photonics, it is also relevant for those working with deep learning in other research domains. We aim at providing a solid starting point to empower researchers to leverage the potential of deep learning in their scientific pursuits.

Differentiating between self-resolving viral infections and bacterial infections in children who are febrile is a common challenge, causing difficulties in identifying which individuals require antibiotics. Studying the host response to infection can provide useful insights and can lead to the identification of biomarkers of infection with diagnostic potential. This study aimed to identify host protein biomarkers for future development into an accurate, rapid point-of-care test that can distinguish between bacterial and viral infections, by recruiting children presenting to health-care settings with fever or a history of fever in the previous 72 h.

The STREAM stage 1 trial showed that a 9-month regimen for the treatment of rifampicin-resistant tuberculosis was non-inferior to the 20-month 2011 WHO-recommended regimen. In STREAM stage 2, we aimed to compare two bedaquiline-containing regimens with the 9-month STREAM stage 1 regimen.

AbstractWe adapt the classical definition of locally stationary processes in discrete time (see e.g. Dahlhaus, ‘Locally stationary processes’, in Time Series Analysis: Methods and Applications(2012)) to the continuous-time setting and obtain equivalent representations in the time and frequency domains. From this, a unique time-varying spectral density is derived using the Wigner–Ville spectrum. As an example, we investigate time-varying Lévy-driven state space processes, including the class of time-varying Lévy-driven CARMA processes. First, the connection between these two classes of processes is examined. Considering a sequence of time-varying Lévy-driven state space processes, we then give sufficient conditions on the coefficient functions that ensure local stationarity with respect to the given definition.

The degradation of materials due to erosion–corrosion occurs on the components that handle particle-laden corrosive slurry. The combined attack of mechanical erosion and corrosion shows increased material loss than the individual action of erosion and corrosion. The synergy accelerates material removal by eroding the corroded surface layer and corroding the surface due to the elimination of the passivating oxide layer by erosion. The synergism of erosion–corrosion is found to be more complex. Further, the coupled effect of mechanical erosion and electrochemical corrosion and the factors influencing erosion–corrosion still needs to be fully investigated. This review aims to provide a general and detailed summary of the interaction between erosion and corrosion of materials for the applications of pump impellers, pipelines for desalination, and oil and gas transportation. Importance is also given to the factors influencing erosion–corrosion, such as erodent particle properties (hardness, size, and shape), slurry properties (particle concentration, pH value, temperature), and flow characteristics (impingement angle, velocity). The various erosion models and the most used apparatus have also been reviewed.

Background Patients with multiple comorbidities often have delayed hip fracture surgery due to medical optimization. The goal of this study is to identify the allowable time for medical optimization in severely ill hip fracture patients.Methods The 2016-2019 NSQIP database was used to identify patients over age 60 with ASA classification scores 3 and 4 for severe and life-threatening systemic diseases. Patients were divided into immediate (<24 hours), early (24-48 hours), or late (>48 hours) groups based on time to surgery (TTS). Risk-adjusted multivariable logistic regressions were conducted to compare relationships between 30-day postoperative outcomes and TTS.Results 43,071 hip fracture cases were analyzed for the purposes of this study. Compared to patients who underwent surgery immediately, patients who had surgeries between 24 and 48 hours were associated with higher rates of pneumonia (OR 1.357, CI 1.194-1.542), UTIs (OR 1.155, CI 1.000-1.224), readmission (OR 1.136, CI 1.041-1.240), postoperative LOS beyond 6 days (OR 1.249, CI 1.165-1.340), and mortality (OR 1.205, CI 1.084-1.338). Patients with surgeries delayed beyond 48 hours were associated with higher rates of CVA (OR 1.542, CI 1.048-2.269), pneumonia (OR 1.886, CI 1.611-2.209), UTIs (OR 1.546, CI 1.283-1.861), readmission (OR 1.212, CI 1.074-1.366), postoperative LOS beyond 6 days (OR 1.829, CI 1.670-2.003), and mortality (OR 1.475, CI 1.286-1.693) compared to patients with immediate surgery.Discussion Severely ill patients with the hip fracture may have a 24-hour window for medical optimization. Hip fracture surgery performed beyond 48 hours is associated with higher complication rates and mortality among those who are severely ill. Further prospective studies are warranted to examine the effects of early surgical intervention among severely ill patients.