Characterization of Rice Yield Based on Biomass and SPAD-Based Leaf Nitrogen for Large Genotype Plots.

The use of Unmanned Aerial Vehicle (UAV) images for biomass and nitrogen estimation offers multiple opportunities for improving rice yields. UAV images provide detailed, high-resolution visual information about vegetation properties, enabling the identification of phenotypic characteristics for selecting the best varieties, improving yield predictions, and supporting ecosystem monitoring and conservation efforts. In this study, an analysis of biomass and nitrogen is conducted on 59 rice plots selected at random from a more extensive trial comprising 400 rice genotypes. A UAV acquires multispectral reflectance channels across a rice field of subplots containing different genotypes. Based on the ground-truth data, yields are characterized for the 59 plots and correlated with the Vegetation Indices (VIs) calculated from the photogrammetric mapping. The VIs are weighted by the segmentation of the plants from the soil and used as a feature matrix to estimate, via machine learning models, the biomass and nitrogen of the selected rice genotypes. The genotype IR 93346 presented the highest yield with a biomass gain of 10,252.78 kg/ha and an average daily biomass gain above 49.92 g/day. The VIs with the highest correlations with the ground-truth variables were NDVI and SAVI for wet biomass, GNDVI and NDVI for dry biomass, GNDVI and SAVI for height, and NDVI and ARVI for nitrogen. The machine learning model that performed best in estimating the variables of the 59 plots was the Gaussian Process Regression (GPR) model with a correlation factor of 0.98 for wet biomass, 0.99 for dry biomass, and 1 for nitrogen. The results presented demonstrate that it is possible to characterize the yields of rice plots containing different genotypes through ground-truth data and VIs.

Geometry Regularized Autoencoders.

A fundamental task in data exploration is to extract low dimensional representations that capture intrinsic geometry in data, especially for faithfully visualizing data in two or three dimensions. Common approaches use kernel methods for manifold learning. However, these methods typically only provide an embedding of the input data and cannot extend naturally to new data points. Autoencoders have also become popular for representation learning. While they naturally compute feature extractors that are extendable to new data and invertible (i.e., reconstructing original features from latent representation), they often fail at representing the intrinsic data geometry compared to kernel-based manifold learning. We present a new method for integrating both approaches by incorporating a geometric regularization term in the bottleneck of the autoencoder. This regularization encourages the learned latent representation to follow the intrinsic data geometry, similar to manifold learning algorithms, while still enabling faithful extension to new data and preserving invertibility. We compare our approach to autoencoder models for manifold learning to provide qualitative and quantitative evidence of our advantages in preserving intrinsic structure, out of sample extension, and reconstruction. Our method is easily implemented for big-data applications, whereas other methods are limited in this regard.

Cost Disclosure of Surgeon "Scorecards": Effects on Operating Room Costs for Total Hip and Knee Arthroplasty.

Background: Rising health care costs, coupled with an emphasis on cost containment, continue to gain importance. Surgeon cost scorecards developed to track case-based expenditures can help surgeons compare themselves with their peers and identify areas of potential quality improvement. Purpose: We sought to investigate what effect surgeon scorecards had on operating room (OR) costs in orthopedic surgery. Methods: Our hospital distributed OR cost scorecards to 4 adult reconstruction fellowship-trained orthopedic surgeons beginning in 2012. The average direct per-case supply cost of procedures was calculated quarterly and collected over a 5-year period, and each surgeon's data were compared with that of their peers. All 4 surgeons were made aware of the costs of other surgeons at the 2-year mark. The initial 2 years of data was compared with that of the final 2 years. Results: The average direct per-case supply cost ranged from $4955 to $5271 for total knee arthroplasty (TKA) and $5469 to $5898 for total hip arthroplasty (THA) during the initial 2-year period. After implementing disclosures, the costs for TKA and THA, respectively, ranged from $4266 to $4515 (14% annual cost savings) and from $5073 to $5727 (5% annual cost savings); 3 of the 4 surgeons said that cost transparency altered their practice. Conclusion: Our comparison suggests that orthopedic surgeons' participation in a program of operative cost disclosure may be useful to them; we found a possible association with reduced per-case costs for TKA and THA at our institution over a 5-year period. More rigorous study that incorporates the effects of the scorecards on patient outcomes is warranted.

Tdnn-Based Engine In-Cylinder Pressure Estimation from Shaft Velocity Spectral Representation.

Pressure is one of the essential variables to give information about engine condition and monitoring. Direct recording of this signal is complex and invasive, while angular velocity can be measured. Nonetheless, the challenge is to predict the cylinder pressure using the shaft kinematics accurately. In this paper, a time-delay neural network (TDNN), interpreted as a finite pulse response (FIR) filter, is proposed to estimate the in-cylinder pressure of a single-cylinder internal combustion engine (ICE) from fluctuations in shaft angular velocity. The experiments are conducted over data obtained from an ICE operating in 12 different states by changing the angular velocity and load. The TDNN's delay is adjusted to get the highest possible correlation-based score. Our methodology can predict pressure with an R2 >0.9, avoiding complicated pre-processing steps.

Short-Term Follow-Up of Patellar Component Revision in Patients With Isolated Patellar Component Loosening.

BACKGROUND: The etiology of patellar component loosening can be multifactorial, including component malposition, trauma, infection, and poor implant design. These cases may be managed with isolated patellar component revision or simultaneous patellar component with femoral and/or tibial component revision. Isolated patellar revision in the setting of aseptic loosening historically has had limited success with high rates of repeat revision. METHODS: We performed a retrospective cohort study of 75 cases diagnosed with patellar component loosening that underwent revision. Patients were followed for a minimum of 2 years. Cases were categorized as either isolated patellar (IP) revision or patellar with femoral and/or tibial component (P + O) revisions. Survivorship and re-revision causes were compared between groups. Secondary outcomes included surgical time, estimated blood loss, range of motion, and length of stay. RESULTS: Fifty patients underwent IP revision, and 25 patients had P + O revision. Overall survivorship at the 2-year follow-up interval was 94.6%. Survivorship of IP revision undertaken for aseptic loosening was 94%. Survivorship of P + O revision was 96%. Eight percent of patients required reoperation from the P + O revision group, while 12% of patients in the IP revision group underwent a reoperation. Patients undergoing IP revision had better postoperative range of motion, lower surgical times, lower estimated blood loss, and decreased length of stay. CONCLUSION: IP revision demonstrates excellent survivorship and clinical outcomes comparable to P + O revision. When appropriate, IP revision should be considered as a potential treatment option. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Impact of Resident Training Level on Radiation Exposure During Fixation of Proximal Femur Fractures.

OBJECTIVE: To identify whether residents are at greater risk of radiation exposure from intraoperative fluoroscopy while earlier in their training and during more complex procedures. METHODS: We analyzed 852 extracapsular proximal femur fracture fixation cases. We compared fluoroscopy times by various levels of resident training, fracture type, and implant used. Attending-only cases were used as a control group. RESULTS: Fluoroscopy times during subtrochanteric fracture fixation (176.1 ± 11.27 seconds) were longer than intertrochanteric (111.4 ± 2.44 seconds) and basicervical fractures (91.49 ± 5.77 seconds). Long nail (150.2 ± 3.75 seconds) times were longer than short (92.3 ± 3.15 seconds) and intermediate (76.45 ± 3.01 seconds) nails. Significantly, more fluoroscopy was used in junior (115.9 ± 4.24 seconds), senior (123.0 ± 6.08 seconds), junior combo (130.6 ± 7.74 seconds), and senior combo cases (131.8 ± 6.11 seconds) compared with the control (94.91 ± 3.91). CONCLUSION: Orthopaedic surgery residents and attendings must remain aware of radiation exposure secondary to intraoperative fluoroscopy. Appropriate personal protective equipment should be worn, and more experienced surgeons should take a more active role in the complex cases to decrease exposure risk. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Simple Protocol to Stratify Pulmonary Risk Reduces Complications After Total Joint Arthroplasty.

BACKGROUND: Pulmonary complications after total joint arthroplasty are a burden to patients and the healthcare system. The aim of this study is to demonstrate the effectiveness of a pulmonary screening questionnaire and intervention protocol developed at our institution to prevent pulmonary complications. METHODS: Between 2010 and 2015, 7658 consecutive total joint arthroplasty patients at our institution were reviewed. Based on our pre-operative pulmonary risk assessment tool, 1625 patients were flagged as high pulmonary risk. Patients were determined to be high risk if they were a current or former heavy smoker with an abnormal spirometry, had a positive obstructive sleep apnea screening, required continuous positive airway pressure/bi-level positive airway pressure use, had a history of significant pulmonary disease, had an oxygen saturation <90%, or had body mass index >40. A standardized monitoring protocol and interventions including smoking cessation, treatment and optimization of primary pulmonary conditions, peri-operative inhaler use, spinal anesthesia, aspiration precautions, elevated head of bed >20° resting and >45° while eating, maintaining oxygen saturation ≥92%, early use of incentive spirometer, avoidance of narcotics and early respiratory therapy consult were initiated for all high risk patients. RESULTS: Only 7 of 7658 (0.091%) patients suffered pulmonary complications after initiating our intervention protocol. These included 3 aspiration pneumonias, 1 asthma exacerbation, 1 chronic obstructive pulmonary disease exacerbation, 1 continuous positive airway pressure intolerance in a patient with obstructive sleep apnea, and 1 requirement of bi-level positive airway pressure. The pulmonary risk questionnaire accurately identified all patients who had pulmonary complications. The overall pulmonary complication rate at our institution decreased from 5.7% to 0.09% after implementing our screening questionnaire and intervention protocol (P < .0001). CONCLUSION: Our results demonstrate a more than 63-fold reduction in pulmonary complications at our institution. Our screening questionnaire and intervention protocol is an effective way of identifying and preventing pulmonary complications.

A Proactive Approach to High Risk Delirium Patients Undergoing Total Joint Arthroplasty.

BACKGROUND: Delirium is a common complication among elderly patients undergoing total joint arthroplasty (TJA). Its incidence has been reported from 4% to 53%. The Centers for Medicare and Medicaid Services consider delirium following TJA a "never-event." The purpose of this study is to evaluate a simple perioperative protocol used to identify delirium risk patients and prevent its incidence following TJA. METHODS: Our group developed a protocol to identify and prevent delirium in patients undergoing TJA. All patients were screened and scored in the preoperative assessment, on criteria such as age, history of forgetfulness, history of agitation or visual hallucinations, history of falls, history of postoperative confusion, and inability to perform higher brain functions. Patients were scored on performance in a simple mental examination. The patients were classified as low, medium, or high risk. Patients who were identified as high risk were enrolled in a delirium avoidance protocol that minimized narcotics and emphasized nursing involvement and fluids administration. RESULTS: Five of 7659 (0.065%) consecutive TJA patients from 2010 to 2015 developed delirium. A total of 422 patients were identified as high risk. All 5 patients who suffered delirium were within the high risk group. No low or medium risk patients suffered a delirium complication. Three (0.039%) patients suffered drug-induced delirium, 1 (0.013%) had delirium related to alcohol withdrawal, and 1 (0.013%) had delirium after a systemic infection. CONCLUSION: This protocol is effective in identifying patients at high delirium risk and diminishing the incidence of this complication by utilizing a simple screening tool and perioperative protocol.

The Direct Anterior Approach Does Not Increase Return to Function Following Hemiarthroplasty for Femoral Neck Fracture.

The purpose of this study was to evaluate functional outcomes for hemiarthroplasty using a direct anterior approach or a direct lateral approach for femoral neck fracture. This retrospective review used data collected from a single institution between 2006 and 2016. Eighty-five and 75 consecutive patients who underwent hemiarthroplasty via a direct anterior approach and a direct lateral approach, respectively, met inclusion criteria. All patients with femoral neck fractures were treated by 1 of 2 fellowship-trained orthopedic surgeons using the direct anterior approach or the direct lateral approach to hemiarthroplasty. Disposition, ambulation, and other perioperative surgical outcomes were compared between the cohorts. Compared with the direct lateral cohort, the direct anterior cohort had a shorter mean operative time (2.4 minutes, P<.01), a shorter mean length of hospital stay (2.7 days, P<.01), and a smaller mean decrease in hemoglobin postoperatively (0.7 g/dL, P<.01). No significant difference was observed between the cohorts for postoperative disposition, the number of feet ambulated on the second postoperative day, or the prevalence of ambulatory decline at 4- to 6-week and 4- to 6-month follow-up visits. Compared with the direct lateral approach, the direct anterior approach may benefit patients by small, but statistically significant, improvements in blood loss, surgical time, and length of hospital stay after hemiarthroplasty. However, the direct anterior approach does not appear to decrease the likelihood of transfer to a skilled nursing facility postoperatively or accelerate return to preoperative function. [Orthopedics. 2017; 40(6):e1055-e1061.].

Is There Still a Role for Irrigation and Debridement With Liner Exchange in Acute Periprosthetic Total Knee Infection?

BACKGROUND: Periprosthetic joint infection (PJI) is an important cause of failure in total knee arthroplasty. Irrigation and debridement including liner exchange (I&D/L) success rates have varied for acute PJI. The purpose of this study is to present results of a specific protocol for I&D/L with retention of total knee arthroplasty components. METHODS: Sixty-seven consecutive I&D/L patients were retrospectively evaluated. Inclusion criteria for I&D/L were as follows: fewer than 3 weeks of symptoms, no immunologic compromise, intact soft tissue sleeve, and well-fixed components. I&D/L consisted of extensive synovectomy; irrigation with 3 L each of betadine, Dakin's, bacitracin, and normal saline solutions; and exchange of the polyethylene component. Postoperatively, all patients were treated with intravenous antibiotics. Infection was considered eradicated if the wound healed without persistent drainage, there was no residual pain or evidence of infection. RESULTS: Forty-six patients (68.66%) had successful infection eradication regardless of bacterial strain. Those with methicillin-resistant Staphylococcus aureus (MRSA) had an 80% failure rate and those with Pseudomonas aeruginosa had a 66.67% failure rate. The success rate for bacteria other than MRSA and Pseudomonas was 85.25%. CONCLUSION: Our protocol for I&D/L was successful in the majority of patients who met strict criteria. We recommend that PJI patients with MRSA or P aeruginosa not undergo I&D/L and be treated with 2-stage revision. For nearly all other patients, our protocol avoids the cost and patient morbidity of a 2-stage revision.

Theory of Inpatient Circadian Care (TICC): A Proposal for a Middle-Range Theory.

The circadian system controls the daily rhythms of a variety of physiological processes. Most organisms show physiological, metabolic and behavioral rhythms that are coupled to environmental signals. In humans, the main synchronizer is the light/dark cycle, although non-photic cues such as food availability, noise, and work schedules are also involved. In a continuously operating hospital, the lack of rhythmicity in these elements can alter the patient's biological rhythms and resilience. This paper presents a Theory of Inpatient Circadian Care (TICC) grounded in circadian principles. We conducted a literature search on biological rhythms, chronobiology, nursing care, and middle-range theories in the databases PubMed, SciELO Public Health, and Google Scholar. The search was performed considering a period of 6 decades from 1950 to 2013. Information was analyzed to look for links between chronobiology concepts and characteristics of inpatient care. TICC aims to integrate multidisciplinary knowledge of biomedical sciences and apply it to clinical practice in a formal way. The conceptual points of this theory are supported by abundant literature related to disease and altered biological rhythms. Our theory will be able to enrich current and future professional practice.