Exploration of Damage Identification Method for a Large-Span Timber Lattice Shell Structure in Taiyuan Botanical Garden based on Structural Health Monitoring.

Large-span spatial lattice structures generally have characteristics such as incomplete modal information, high modal density, and high degrees of freedom. To address the problem of misjudgment in the damage detection of large-span spatial structures caused by these characteristics, this paper proposed a damage identification method based on time series models. Firstly, the order of the autoregressive moving average (ARMA) model was selected based on the Akaike information criterion (AIC). Then, the long autoregressive method was used to estimate the parameters of the ARMA model and extract the residual sequence of the autocorrelation part of the model. Furthermore, principal component analysis (PCA) was introduced to reduce the dimensionality of the model while retaining the characteristic values. Finally, the Mahalanobis distance (MD) was used to construct the damage sensitive feature (DSF). The dome of Taiyuan Botanical Garden in China is one of the largest non-triangular timber lattice shells worldwide. Relying on the structural health monitoring (SHM) project of this structure, this paper verified the effectiveness of the damage identification model through numerical simulation and determined the damage degree of the dome structure through SHM measurement data. The results demonstrated that the proposed damage identification method can effectively identify the damage of large-span timber lattice structures, locate the damage position, and estimate the degree of damage. The constructed DSF had relatively strong robustness to small damage and environmental noise and has practical application value for SHM in engineering.

Confusion assessment method accurately screens for hepatic encephalopathy and predicts short-term mortality in hospitalized patients with cirrhosis.

Hepatic encephalopathy (HE), a subtype of delirium, is common in cirrhosis and associated with poor outcomes. Yet, objective bedside screening tools for HE are lacking. We examined the relationship between an established screening tool for delirium, Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and short-term outcomes while comparing its performance with previously established measures of cognitive function such as West Haven criteria (WHC). Prospectively enrolled adults with cirrhosis who completed the CAM-ICU from 6/2014-6/2018 were followed for 90 days. Blinded provider-assigned West Haven Criteria (WHC) and other measures of cognitive function were collected. Logistic regression was used to test associations between CAM-ICU status and outcomes. Mortality prediction by CAM-ICU status was assessed using Area under the Receiver Operating Characteristics curves (AUROC). Of 469 participants, 11% were CAM-ICU( +), 55% were male and 94% were White. Most patients were Childs-Pugh class C (59%). CAM-ICU had excellent agreement with WHC (Kappa = 0.79). CAM-ICU( +) participants had similar demographic features to those CAM-ICU(-), but had higher MELD (25 vs. 19, p < 0.0001), were more often admitted to the ICU (28% vs. 7%, p < 0.0001), and were more likely to be admitted for HE and infection. CAM-ICU( +) participants had higher mortality (inpatient:37% vs. 3%, 30-day:51% vs. 11%, 90-day:63% vs. 23%, p < 0.001). CAM-ICU status predicted mortality with AUROC of 0.85, 0.82 and 0.77 for inpatient, 30-day and 90-day mortality, respectively. CAM-ICU easily screens for delirium/HE, has excellent agreement with WHC, and identifies a hospitalized cirrhosis cohort with high short-term mortality.

Daily Costs and Cost Effectiveness of Glaucoma Fixed Combinations in China.

BACKGROUND: The aim of this study was to compare the daily costs and cost effectiveness of fixed combination glaucoma drugs in China. METHODS: This study included the following fixed combination drugs: brinzolamide 1% and timolol 0.5% (Azarga; Alcon, Inc., Fort Worth, TX, USA), travoprost 0.004% and timolol 0.5% (DuoTrav; Alcon, Inc.), bimatoprost 0.03% and timolol 0.5% (Ganfort; Allergan, Inc., Dublin, Ireland), and latanoprost 0.005% and timolol 0.5% (Xalacom; Pfizer, Inc., New York, NY, USA). Five bottles of each drug were measured. The mean actual volume, mean actual number of drops, volume per drop, daily cost, yearly cost, and per mmHg reduction cost for each drug were calculated. RESULTS: The volumes per drop ranged from 32.61 ± 2.90 µl (DuoTrav) to 24.38 ± 0.23 µl (Ganfort). The number of usage days per bottle varied from 36 days (DuoTrav) to 61 days (Ganfort). Azarga had the lowest daily cost ($0.23) and yearly cost ($84.72), while DuoTrav had the highest daily cost ($0.79) and yearly cost ($287.02). Azarga costed $2.17-$3.30 per mmHg intraocular pressure reduction, which was lower than the other three drugs. For the prostaglandin and ß-adrenergic blocker FCs, Ganfort had the lowest daily cost ($0.35) and per mmHg reduction cost (from $3.40 to $4.04). CONCLUSIONS: The daily costs of these drugs were significantly different, with Azarga having the lowest daily cost and best cost effectiveness. For the prostaglandin and ß-adrenergic blocker fixed combinations, Ganfort was the most economical choice with its lower daily cost and per mmHg reduction cost. The results of this study could provide drug selection guidance from an economic perspective, but various factors should be considered when making a decision.