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Abstract The goal of this work is to develop a Machine Learning model to predict the need for both invasive and non‐invasive mechanical ventilation in intensive care unit (ICU) patients. Using the Philips eICU Research Institute (ERI) database, 2.6 million ICU patient data from 2010 to 2019 were analyzed. This data was randomly split into training (63%), validation (27%), and test (10%) sets. Additionally, an external test set from a single hospital from the ERI database was employed to assess the model's generalizability. Model performance was determined by comparing the model probability predictions with the actual incidence of ventilation use, either invasive or non‐invasive. The model demonstrated a prediction performance with an AUC of 0.921 for overall ventilation, 0.937 for invasive, and 0.827 for non‐invasive. Factors such as high Glasgow Coma Scores, younger age, lower BMI, and lower PaCO2 were highlighted as indicators of a lower likelihood for the need for ventilation. The model can serve as a retrospective benchmarking tool for hospitals to assess ICU performance concerning mechanical ventilation necessity. It also enables analysis of ventilation strategy trends and risk‐adjusted comparisons, with potential for future testing as a clinical decision tool for optimizing ICU ventilation management.

Intradermal delivery of DNA vaccines via electroporation (ID-EP) has shown clinical promise, but the use of needle electrodes is typically required to achieve consistent results. Here, delivery of a DNA vaccine targeting the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is achieved using noninvasive intradermal vacuum-EP (ID-VEP), which functions by pulling a small volume of skin tissue into a vacuum chamber containing noninvasive electrodes to perform EP at the injection site. Gene expression and immunogenicity correlated with EP parameters and vacuum chamber geometry in guinea pigs. ID-VEP generated potent humoral and cellular immune responses across multiple studies, while vacuum (without EP) greatly enhanced localized transfection but did not improve immunogenicity. Because EP was performed noninvasively, the only treatment site reaction observed was transient redness, and ID-VEP immune responses were comparable to a clinical needle-based ID-EP device. The ID-VEP delivery procedure is straightforward and highly repeatable, without any dependence on operator technique. This work demonstrates a novel, reliable, and needle-free delivery method for DNA vaccines.

Abstract Background The purpose of this study was to investigate the fracture strength and stress distribution of four ceramic restorations. Methods Forty human mandibular first molars were collected and randomized into four groups after establishing the distal defect: full crown group with 4 mm axial wall height (AWH) (FC4); short AWH crown group with 2 mm AWH (SC2); occlusal veneer group with 0 mm AWH (OV0); occlusal distal veneer group with only the distal surface prepared, and 4 mm AWH (OD4). The teeth were prepared according to the groups and the ceramic restorations were completed using celtra duo ceramic blocks. The ceramic thickness of the occlusal surface is about 1.5 mm and the edge is about 1 mm. The failure load values and fracture modes of each group were detected by mechanical test in vitro. According to the groups to establish three-dimensional finite element analysis (FEA) models, a 600 N loading force was applied vertically using a hemispherical indenter with a diameter of 6 mm. and compare the stress distribution under the condition of different restorations. Results In vitro mechanical tests showed that the failure load values were SC2 (3232.80 ± 708.12 N) > OD4 (2886.90 ± 338.72 N) > VO0 (2133.20 ± 376.15 N) > FC4(1635.40 ± 413.05 N). The failure load values of the short AWH crown and occlusal distal veneer were significantly higher than that of occlusal veneer and full crown (P VO0 (214.3 MPa) > OD4 (197.9 MPa) > SC2 (163.1 MPa). The stress of enamel was concentrated in the area where the remaining enamel was thinner, the maximum von Mises stress values was OD4 (246.2 MPa) ≈ FC4 (212.4 MPa) > VO0 (61.8 MPa) ≈ SC2 (45.81 MPa). The stress of dentin is concentrated in the root furcation and the upper third region of the root. However, stress concentration was observed at the tooth cervix in the full crown. Conclusion Under certain conditions, the occlusal distal veneer shows better performance than the full crown.

Predicting the duration of ventilation in the ICU helps in assessing the risk of ventilator-induced lung injury, ensuring sufficient oxygenation, and optimizing resource allocation. Prior models provided a prediction of total duration without distinguishing between invasive and non-invasive ventilation. This work proposes two independent gradient boosting regression models for predicting the duration of invasive and non-invasive ventilation based on commonly available ICU features. These models are trained on 2.6 million patient stays across 350 US hospitals between 2010 to 2019. The mean absolute error (MAE) for the prediction of duration was 2.08 days for invasive ventilation and 0.36 days for non-invasive ventilation. The total ventilation duration predicted by our model had MAE of 2.38 days, which outperformed the gold standard (APACHE) with MAE of 3.02 days. The feature importance analysis of the trained models showed that, for invasive ventilation, high average heart rate, diagnosis of respiratory infection and admissions from locations other than the operating room were associated with longer ventilation durations. For non-invasive ventilation, higher respiratory rates and having any GCS measurement were associated with longer durations.

4Cr5MoSiV (H11) steel machining chips were crushed to a powder and then consolidated into discs by hot pressing under various consolidation parameters. The discs were subjected to modified spheroidizing annealing treatment, and their evolved microstructure, tensile mechanical properties and fracture behavior were studied. The microstructure consisted of α−Fe as a matrix, together with heterogeneously distributed non metallic inclusions from the chip-crushing step and precipitated secondary phases. The yield strength, fracture strength and elongation to fracture of the consolidated discs were determined to be in the range of 215∼264 ​MPa, 344∼415 ​MPa and 1.2∼2.6%, respectively. The strength of the recycled H11 steel was comparable with that of the ingot metallurgy (IM) H11 steel, but the tensile ductility of the former was significantly lower than that of the latter, being mainly caused by the fracture of the non-metallic inclusions along with the hard secondary phase particles in the IM H11 steel which leads to premature fracture of the samples. The Vickers hardness of the samples were in the range of 144∼194 HV being comparable to that of the IM counterpart. Factographs of the fracture surface demonstrated that the tensile test specimens fractured in a brittle fracture mode.

The Sinian Dengying Fm in the Sichuan Basin is a set of fractured-vuggy reservoirs mainly dominated by sedimentation and karstification, and characterized by small fractures and vugs, complex stratigraphy and lithology, and strong vertical and lateral reservoir heterogeneity. As a result, the drilling rates are lower and single-well gas productivity varies greatly there. And the reservoir identification results based on seismic data in this area are ambiguous. In view of this, the Deng 4 Member in the Gaoshiti buried structure on the southern flank of the Leshan–Longnüsi palaeohigh was precisely divided in stratigraphy. Then, the types of reservoir assemblages were determined based on gas well logging and test data, and the seismic response characteristics of typical wells with different types of reservoir assemblages and the seismic modes of high productivity wells were studied by using high-resolution seismic data. It is indicated that the Deng 4 Member in this area is divided into three types of reservoir assemblages, which correspond to three seismic modes. Seismic mode I: It presents the seismic response characteristics of “wide wave troughs + double highlights” or “wide wave troughs + complex waves”, indicating that fractures and vugs are developed. It is the preferred seismic mode of high productivity wells in the stage of development. In this mode, the technology of highly deviated wells or horizontal wells can be implemented. Seismic mode II: It presents the seismic response characteristics of “wide wave troughs”, indicating that fractures and vugs are relatively developed. It is the mode of moderate productivity wells. In this mode, the technology of highly deviated wells can be implemented. Seismic mode III: It presents the seismic response characteristics of “wide wave troughs + highlights”, indicating that fractures and vugs are underdeveloped. It is mode of low productivity wells, in which the technology of horizontal wells can be implemented. The new understandings on seismic modes were applied on site. It is shown that the reservoir drilling rate is over 60% and the average gas production rate during the production test of 8 wells is up to 75.34 × 104 m3/d. It is concluded that the seismic mode of high productivity wells based on seismic facies, fracture and vug prediction and integrated target design provides a support for the well arrangement and drilling trajectory adjustment in natural gas exploration and development in the Gaoshiti area and good results have been achieved. Keywords: Sichuan Basin, Gaoshiti area, Sinian, Dengying Formation, Karst, Fractured-vuggy reservoir, Seismic response, Seismic mode of high productivity well, Fracture and vug prediction

A high-precision wavelength demodulation method based on optical fiber Fabry-Perot tunable (FPT) filter is proposed for the fiber Bragg grating temperature sensing system. This algorithm uses the original sampling data obtained from the data acquisition card to simultaneously calculate the transmission spectrum of the F-P etalon (FPE) and the reflection spectrum of the fiber Bragg grating (FPG) sensors. In each scanning cycle, the transmission spectrum wavelength of the F-P etalon (FPE) is calibrated dynamically in real time, the reflectance spectrum central wavelength of the FPE sensors is calculated by referring to the transmission spectrum wavelength of the FPE that has been calibrated. It effectively weakens the perturbation effect caused by the nonlinear and non-reproducibility of narrowband light source from the fiber FPT filter, reduces the numerical error and effectively eliminates the pseudo peak of the FPE, and greatly improves the measurement accuracy of the system. Most programming languages can implement this algorithm. A temperature sensing experiment for the proposed method has been carried out. Results showed that the demodulation precision by our method could reach up to ±0.2 °C, wavelength demodulation accuracy 3 pm.

The petrophysical and logging response characteristics of asphaltene carbonate reservoirs were examined based on the measurement of porosity and permeability, density, compressional and shear wave slowness, resistivity and Nuclear Magnetic Resonance transverse relaxation time (T2) of cores before and after the bitumen dissolving. The results show that (1) the asphalt can damage the pore structure of the reservoir and cause reduction of effective reservoir space and permeability; (2) with the increase of asphalt content, the compression and shear wave slowness generally decrease while the density and resistivity increase; (3) with the increase of asphalt content, the compressional wave slowness and density change less, while the shear wave slowness and resistivity change larger; and (4) the T2 values of asphalt are generally less than 3 ms, and the higher the maturity of the asphalt, the lower the T2 value. Based on these experiments, a method based on conventional and special logging methods was presented to evaluate asphalt content, effective porosity and water saturation in asphaltene carbonate reservoirs. The method has already been applied to 80 wells in the Longwangmiao Formation of the Anyue gas field in the Sichuan Basin to pick out zones rich in asphalt on the plane, which has effectively guided the selection of well location in the gas reservoir development. Key words: Sichuan Basin, Cambrian Longwangmiao Formation, asphalt, carbonate reservoir, nuclear magnetic resonance logging, petrophysical properties, logging evaluation

Abstract Background To avoid untoward changes when primary teeth are replaced by permanent teeth, resorption of the material used in primary teeth root canal filling should occur at the same rate as root resorption. The Aim of this study was to compare the success rates of a mixed primary root canal filling (MPRCF, ingredients: zinc oxide–eugenol [ZOE], iodoform, calcium hydroxide) to those of ZOE and Vitapex in pulpectomised primary molars. Methods One hundred and sixty primary molars from 155 children (average age 5.88 ± 1.27 years) underwent two-visit pulpectomy using one of the three materials. The clinical and radiographic findings at 6, 12 and 18 months were assessed. Results At 6 and 12 months, the MPRCF and ZOE success rates were 100%. The Vitapex group showed clinical success rate and radiographic success rate of 100 and 94.5% at 6 months, and 80.4 and 60.7% at 12 months. The 18-month clinical success rates of the MPRCF, ZOE and Vitapex were 96.2, 92.2 and 71.4% and radiographic success rates were 92.5, 88.2 and 53.6%, respectively. There was a statistically significant difference in the success rates between MPRCF and Vitapex and no significant differences between MPRCF and ZOE. More MPRCF were resorbed at same rate with roots than ZOE and Vitapex. Early resorption of root filling resulted in more failure. Conclusions The mixture of ZOE, iodoform and calcium hydroxide can be considered an effective root canal filling material in pulp involved primary teeth and had no adverse effect on tooth replacement. Trial registration ChiCTR-TRC-14004938 . Registered 13 July 2014.

We propose a real-time parallel data acquisition and big data processing method. This method can multiplex different types of fiber sensors and quickly complete the simultaneous sampling of thousands of sensors on hundreds of channels in four-parameter heterogeneous fiber sensor network, its sampling frequency is up to 6.4MHz, and the data throughput is up to 13.8MB/s. This method is three times faster than the usual method.

Objectives: Evaluate the accuracy of different ICU risk models repurposed as continuous markers of severity of illness.Design: Nonintervention cohort study.Setting: eICU Research Institute ICUs using tele-ICU software calculating continuous ICU Discharge Readiness Scores between January 2013 and March 2016.Patients: Five hundred sixty-one thousand four hundred seventy-eight adult ICU patients with an ICU length of stay between 4 hours and 30 days.Interventions: Not available.Measurements and Main Results: Hourly Acute Physiology and Chronic Health Evaluation IV, Sequential Organ Failure Assessment, and Discharge Readiness Scores were calculated beginning hour 4 of the ICU stay. Primary outcome was the area under the receiver operating characteristic curve for the mean score with ICU mortality. Secondary outcomes included area under the receiver operating characteristic curves for ICU mortality with admission, median, maximum and last scores, and for death within 24 hours. The trajectories of each score were visualized by plotting the hourly averages against time in the ICU, stratified by mortality and length of stay. The area under the receiver operating characteristic curves for mean Acute Physiology and Chronic Health Evaluation, Sequential Organ Failure Assessment, and Discharge Readiness Scores were 0.90 (0.89-0.90), 0.86 (0.86-0.86), and 0.94 (0.94-0.94), respectively. The area under the receiver operating characteristic curves for hourly Acute Physiology and Chronic Health Evaluation, Sequential Organ Failure Assessment, and Discharge Readiness Scores predicting 24-hour mortality were 0.81 (0.81-0.81), 0.76 (0.76-0.76), and 0.86 (0.86-0.86). Discharge Readiness Scores had a higher area under the receiver operating characteristic curve than both Acute Physiology and Chronic Health Evaluation and Sequential Organ Failure Assessment for each metric. Acute Physiology and Chronic Health Evaluation and Sequential Organ Failure Assessment scores increased throughout the first 24 hours in both survivors and nonsurvivors; Discharge Readiness Scores continuously decreased in survivors and temporarily decreased before increasing by hour 36 in nonsurvivors with longer length of stays.Conclusions: Acute Physiology and Chronic Health Evaluation, Sequential Organ Failure Assessment, and Discharge Readiness Scores all have relatively high discrimination for ICU mortality when used continuously; Discharge Readiness Scores tended to have slightly higher area under the receiver operating characteristic curves for each endpoint. These findings validate the use of these models on a population level for continuous risk adjustment in the ICU, although Acute Physiology and Chronic Health Evaluation and Sequential Organ Failure Assessment appear slower to respond to improvements in patient status than Discharge Readiness Scores, and Discharge Readiness Scores may reflect physiologic improvement from interventions, potentially underestimating risk. [ABSTRACT FROM AUTHOR]

Objective: To synthesize the existing literature on benefits and risks of anticoagulant use after traumatic brain injury (TBI). Design: Systematic review. A literature search was performed in MEDLINE, International Pharmaceutical Abstracts, Health Star, and CINAHL (Cumulative Index to Nursing and Allied Health Literature) on October 11, 2012, and updated on September 2, 2013, using terms related to TBI and anticoagulants. Main Measures: Human studies evaluating the effects of post-TBI anticoagulation on venous thromboembolism, hemorrhage, mortality, or coagulation parameters with original analyses were eligible for the review. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guideline was followed throughout the conduct of the review. Results: Thirty-nine eligible studies were identified from the literature, of which 23 studies with complete information on post-TBI anticoagulant use and patient outcomes were summarized in this review. Meta-analysis was unwarranted because of varying methodological design and quality of the studies. Twenty-one studies focused on the effects of pharmacological thromboprophylaxis (PTP) post-TBI on venous thromboembolism and/or progression of intracranial hemorrhage, whereas 2 randomized controlled trials analyzed coagulation parameters as the result of anticoagulation. Conclusion: Pharmacological thromboprophylaxis appears to be safe among TBI patients with stabilized hemorrhagic patterns. More evidence is needed regarding effectiveness of PTP in preventing venous thromboembolism as well as preferred agent, dose, and timing for PTP. [ABSTRACT FROM AUTHOR]

The article focuses on a national analysis of incidence rates of depression among older adults after experiencing traumatic brain injury (TBI). It presents the primary sources of data, comorbidities, and data analysis technique. Results in terms of incidence rate of depression before hospital admission, right after hospital discharge and 12 months after TBI, and predictors of depression after TBI are also mentioned.

The article presents the study which examined the optimal technique in the management of venous thromboembolism (VTE) in critically ill adult patients. It claims that VTE prophylaxis was recommended in the ninth edition of the American College of Chest Physicians Antithrombotic Therapy and Prevention of Thrombosis guidelines. Based on the results, patients managed with prophylactic anticoagulation therapy had lower risk of death than those treated with mechanical device prophylaxis.

BACKGROUND: The effect of the respiratory therapist (RT)/patient ratio and RT organizational factors on respiratory resource utilization is unknown. We describe the impact of a multi-component intervention that called for an increase in RT/patient ratio (1:14 to 1:10), improved RT orientation, and formation of a core staffing model on best practice, including spontaneous breathing trials (SBTs) and catheter and bronchoscopically directed lower respiratory tract cultures, or bronchoalveolar lavage (BAL), in both ventilated and non-ventilated patients in the ICU. METHODS: We conducted a single center, quasi-experimental study comparing 651 patients with single and first admissions between April 19, 2005 and April 18, 2006 before the RT services reorganization with 1,073 patients with single and first admissions between September 16, 2007 and September 4, 2008. Baseline characteristics were compared, along with SBTs, BAL use, lower respiratory tract cultures, and chest physiotherapy. RESULTS: Patients in the 2 groups were similar in terms of age (52.9 ± 15.8 y vs 53.9 ± 16.4 y, P ± .23), comorbidity as measured by Charlson score (2.8 ± 2.6 vs 2.8 ± 2.7, P ± .56), and acuity of illness as measured by the Case Mix Index (3.2 ± 3.9 vs 3.3 ± 4.1, P ± .47). Mechanically ventilated patients had similar prevalences of respiratory diseases (24.2% vs 25.1%, P ± .61). There was an increase in SBTs (0.5% vs 73.1%, P < .001), chest physiotherapy (7.4% vs 21.6%, P < .001), BALs (24.0% vs 41.4%, P < .001), and lower respiratory tract cultures (21.5% vs 38.0%, P < .001) in mechanically ventilated patients post-intervention. CONCLUSIONS: A multi-component intervention, including an increase in RT/ patient ratio, improved RT orientation, and establishment of a core staffing model, was associated with increased respiratory resource utilization and evidence-based practice, specifically BALs and SBTs. [ABSTRACT FROM AUTHOR]

Purpose: Guidelines for the construction of critical care units require windows in room design to ensure a contribution of natural sunlight to ambient lighting. However, few studies have been published with evidence assessing this recommendation. We investigated the association of ambient light levels with clinical outcomes and sedative/analgesic/neuroleptic use in a medical intensive care unit (MICU). Methods: This is a retrospective, observational study at a tertiary care facility with a 29-bed MICU. First/single MICU admissions between April 19, 2006, and June 30, 2009 (N = 3577), were analyzed with respect to clinical outcomes and sedation use according to MICU room orientation and corresponding light levels. Results: Light levels were low but varied among the 4 room orientations. There were no significant differences in MICU mortality (north, 14.0%; east, 13.5%; west, 16.2%; south, 15.6%; P = .451), hospital mortality (20.8%, 20.9%, 22.2%, 22.3%; P = .796), 28-day intensive care unit-free days (17.6 ± 10.2, 18.0 ± 10.1, 17.7 ± 10.5, 17.2 ± 10.4; P = .555), 28-day ventilator-free days (16.3 ± 11.1, 16.5 ± 11.1, 15.5 ± 11.5, 15.4 ± 11.4; P = .273). No clinically significant differences in intravenous sedative/analgesic use occurred across room orientations. Conclusions: Despite differing ambient light, room orientation was not associated with critical care outcomes or differences in sedative/analgesic/neuroleptic use. Current guidelines positing that windows alone are necessary or sufficient for MICU room light management may require further investigation and consideration. [ABSTRACT FROM AUTHOR]

The article discusses a study on the prevalence of learned helplessness among families and surrogate decision-makers (SDMs) of patients in intensive care units (ICUs). The study used the Learned Helpness Scale and Perceived Stress Scale to assess the psychologic state of families and SDMs of patients in ICUs at the University of Maryland Medical Center in Baltimore. The study found that lower education levels and increased stress levels are among the risk factors for learned helplessness.

Background: Women compose half of all medical students but are underrepresented in the field of general surgery. Concerns about childbirth and pregnancy during training and practice are factors that may dissuade women from electing a career in surgery. Objective: To assess experiences related to childbirth and pregnancy among women general surgeons. Design: Survey questionnaire. Setting: Self-administered survey sent individually to women surgeons in training and practice. Participants: Women members of the Association for Women Surgeons or the American College of Surgeons who graduated from medical school and practice general surgery or a general surgery subspecialty. Main Outcome Measures: Descriptive data on the timing of pregnancy and perception of stigma attending childbirth and pregnancy as experienced by women surgeons, according to date of medical school graduation (0-9 years since graduation, 10-19 years, 20-29 years, and ⩾30 years). The survey response rate was 49.6%. Trends over time were evaluated using comparisons of proportions and the Cochrane-Armitage trend tests across age cohorts. Results: The perception of stigma associated with pregnancy during training remained large but decreased from 76% in the most remote cohort to 67% in the most recent graduation cohort (P<.001). External influences, even women resident colleagues, were perceived as evincing negative instead of encouraging attitudes toward childbearing during residency, though less so than men, both resident colleagues and faculty. Frequency of pregnancy and pregnancies earlier in training increased over the time cohorts. Conclusions: The number of women general surgeons becoming pregnant during training has increased in recent years; however, substantial negative bias persists. Although the overall magnitude of perceived negative attitudes is greater among male peers than female peers and among faculty than peers, even women residents hold negative views of pregnancy among their colleagues during training. More than half of all women surgeons delay childbearing until they are in independent practice, post-training. Surgical residents and faculty of both sexes exerted negative influences with regard to consideration of childbearing. There was also a trend toward increased childbearing in more recent graduates [ABSTRACT FROM AUTHOR]

The article discusses findings of a study which determined whether a multi-component intervention can minimize patient mortality in a high-intensity, Leapfrog-compliant medical intensive care unit. Included in a multi-component intervention are the transfer from a 10-bed to a 29-bed medical intensive care unit, the initiation of a 24-hour critical care specialist coverage in the medical intensive care unit, and an increase in the respiratory therapist:patient ratio. The study also found that a reorganization of care results to improvement in outcome.

BACKGROUND: Clinical guidelines recommend a restrictive transfusion strategy in nonhemorrhaging critically ill patients. STUDY DESIGN AND METHODS: We conducted a retrospective observational study of 3533 single-admission patients, without evidence of acute coronary syndromes, hemorrhage, or hemoglobinopathy admitted to the medical intensive care unit (MICU) of a large, academic medical center. RESULTS: MICU admission hemoglobin (Hb) level did not change significantly over the study period. The proportion of transfused patients decreased from 31.0% in 1997 to 1998 to 18.0% in 2006 to 2007 (p < 0.001). Among patients receiving transfusion, the mean pretransfusion Hb level decreased over time from 7.9 ± 1.3 to 7.3 ± 1.3 g/dL (p < 0.001). These changes in practice were not accounted for by differences in patient characteristics. The mean nadir Hb level in nontransfused patients decreased from 11.2 ± 2.2 g/dL in 1997 to 1999 to 10.4 ± 2.3 g/dL in 2006 to 2007 (p < 0.001). The mean number of units per patient transfused decreased during this time from 4.3 ± 4.7 to 3.0 ± 3.8 units (p < 0.001). The proportion of transfused patients who were transfused at a Hb level of less than 7.0 g/dL increased by an estimated absolute increment of 3.2% (95% CI, 2.1%-4.3%) per interval (p < 0.001), and the proportion of single-unit transfusions during the first transfusion episode increased by 1.4% per interval (95% CI, 0.2 to 2.6%; p = 0.03) from 40.2% in 1997 to 1998 to 53.1% in 2006 to 2007. CONCLUSIONS: Between 1997 and 2007, important and sustained changes have occurred in our MICU physician transfusion practices, with overall reductions in the proportion of patients transfused, mean pretransfusion Hb level, and nadir Hb level in patients who were not transfused. [ABSTRACT FROM AUTHOR]