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The complex permittivity and permeability of La0.7Sr0.3MnO3 (LSMO)-epoxy composite absorbers are investigated in the microwave ranges from 2 to 18 GHz by transmission/reflection method. A negative magnetic susceptibility of perovskite oxides has been obtained in the frequency range of 4-18 GHz. By the use of the cavity perturbation technique, the negative magnetic susceptibility for 7.5-14 GHz is reconfirmed. For LSMO-epoxy composite with 80 wt % fillers, the maximum reflection loss can reach 23 dB at 10.5 GHz and the absorbing bandwidth above 10 dB is 1.5 GHz with 2 mm thickness. [ABSTRACT FROM AUTHOR]

In this study, the influence of the addition of carbon nanotube (CNT) (0, 0.5, 1.0, and 2.0 wt %) on complex permittivity, complex permeability, and reflection loss for La0.7Sr0.3MnO3-δ (LSMO)/ polymer composites was investigated. Microwave absorbing composites were prepared by molding and curing a mixture of LSMO powders, CNTs, and epoxy resin. The complex permittivity and complex permeability for LSMO/CNT composites were examined by a cavity perturbation technique. The experimental results showed that the complex permittivity increased with increasing CNT addition and the imaginary part of the permeability decreased with rising frequency. In the present study, a microwave absorbing composite filled with 80 wt % LSOM powders and 2 wt % CNTs exhibited the optimum performance, that is, the microwave absorbing peak was -22.85 dB at 9.5 GHz and the -10 dB absorbing bandwidth reached 3.3 GHz for the sample with a matching thickness of 3 mm. [ABSTRACT FROM AUTHOR]

A cavity perturbation resonance technique is used to determine the complex permittivity and permeability of iron-based composite absorbers prepared by mixing various weight percentages of carbonyl iron powder with epoxy as the matrix. The complex permittivity ([variant_greek_epsilon]′-j[variant_greek_epsilon]″) and permeability (μ′-jμ″) are measured around X-band (7–12.5 GHz for permittivity and 7.5–14 GHz for permeability) by the cavity perturbation resonance technique and the results are compared with those obtained by the transmission/reflection method. Experimental results show that the average differences of real parts of permittivity ([variant_greek_epsilon]′) and real and imaginary parts of permeability (μ′ and μ″) measured by these two techniques are less than 10%. The differences in [variant_greek_epsilon]″, however, is apparently higher than the others. As a general trend, the difference increases with increasing weight percentage of carbonyl iron. [ABSTRACT FROM AUTHOR]

This paper investigates the contact ellipse of a helical gear set, composed of an involute pinion and a modified circular-arc gear based on curvature analysis. This gear drive exhibits point contact and parabolic transmission error due to the double crowning effect of the gear, i.e. crowning in both profile and longitudinal directions. The principal directions and curvatures of the generating tool surfaces were derived by means of differential geometry and Rodrigues' equation. The principal directions and curvatures of the pinion and gear surfaces were obtained directly from the generating surfaces. Finally, the determination of the contact ellipses of the mating tooth surfaces was achieved. Numerical examples are also provided to demonstrate the computational results. [ABSTRACT FROM AUTHOR]

A new architecture is proposed for analogue median filters; without the high accuracy reference voltage, high speed analogue summer, and linear sawtooth wave generator; therefore it is easy to implement by VLSI technology. The features of this architecture are modular, regular, locally connected and expansible. The throughput is independent of the window size and the hardware complexity is linearly dependent on the window size. [ABSTRACT FROM AUTHOR]

Examines trends and various types of industrial restructuring in Taiwan. Triggers of industrial restructuring; Corporate strategies that are in response to the decreasing competitiveness in international market; Role of the government in policy responses to industrial restructuring.

Provides information on the development of an efficient rapid convergent control algorithm using a plate-cavity system. Information on the numerical simulation setup; Indepth look at control algorithms; Conclusion reached on the development.

Surface modified iron nanowire nanoparticles were prepared via reduction of iron salts (FeCl3· 6H2O) under an applied magnetic field. To minimize the surface oxidation, dextran (0.05 and 0.25 wt. %) was added during the process and formed a thin passive layer over iron nanowires with alcohol and acetone used to wash iron nanowires. The complex permittivity (&eh;′-j&eh;′′) and permeability (μ′-jμ″) of absorbers are measured by a cavity perturbation method from 7 to 14 GHz. In the present study, the iron nanowire prepared with 0.25 wt. % dextran and washed by acetone (D25AC) exhibited the best microwave absorption performance. Depending on the test frequency, D25AC possessed the largest permittivity loss ranged from 0.14 to 0.17 and relatively small permeability loss (<0.05). Its high permittivity dissipation is responsible for the excellent microwave absorption performance where the reflection loss was-7.7 dB at a matching frequency of 9.0 GHz. [ABSTRACT FROM AUTHOR]

Due to recent rapid commercial and industrial development, mechanical equipment is supplemented massively in the factory and thus mechanical operation causes noise which distresses living at home. In livelihood, neighborhood, transportation equipment, jobsite construction noises impact on quality of life not only factory noise. This study aims to preparation technique and property evaluation of porous sound-absorbing/thermal-insulating composites. Hollow three-dimensional crimp PET fibers blended with low-melting PET fibers were fabricated into hollow PET/low-melting PET nonwoven after opening, blending, carding, lapping and needle-bonding process. Then, hollow PET/low-melting PET nonwovens were laminated into sound-absorbing/thermal-insulating composites by changing sequence of needle-bonding and thermal-treatment. The optimal thermal-treated sequence was found by tensile strength, tearing strength, sound-absorbing coefficient and thermal conductivity coefficient tests of porous composites.

The objective of this study was to examine the effects of follicular cells on the in vitro development of porcine preantral follicles. In Experiment 1, one preantral follicle alone (Trt 1) was cocultured with a follicle of the same size with oocytes (Trt 2) or without oocytes (Trt 3). Preantral follicles cultured alone in vitro for 12 days had greater follicle diameters (1017±96 μm versus 706±69 or 793±72 μm, P<0.05), growth rates (201±0.3 versus 103±0.2 or 128±0.2, P<0.05) and oocyte survival rates (73% versus 48, or 25%, P<0.05) than other groups. The inhibitory effects of follicle cells on the growth of preantral follicles and oocyte survival rates were not enhanced by the addition of oocytectomized preantral follicles (Experiment 2). Follicles were cocultured with different sources of follicular cells in other experiments. Coculture with cumulus cells enhanced oocyte survival compared to the control (without coculture) and mural follicular cell groups (Experiment 3). The growth and survival rates of oocytes collected from the group of follicles cocultured with cumulus cells from large antral follicles (>3 mm) were greater (P<0.05) than those from small antral follicles (<3 mm), or than the control group (without cumulus cells, experiment 4). No significant differences in the follicular diameters (674±30 μm versus 638±33 and 655±28 μm) and growth rate (105% versus 94 and 105%) were observed among the preantral follicles of the different treatments (P>0.05). Taken together, coculture with the cells from large antral follicles (>3 mm) exerted a significant positive effect on oocyte survival. The growth and oocyte survival of preantral follicle cocultured with the same size of follicles (with or without oocyte) were inhibited. Growth and survival rates of preantral follicles and oocytes are improved by coculturing them with the cumulus cells derived from larger antral follicles. [Copyright &y& Elsevier]

Background & Aims: Guidelines recommend use of risk stratification scores for patients presenting with gastrointestinal bleeding (GIB) to identify very-low-risk patients eligible for discharge from emergency departments. Machine learning models may outperform existing scores and can be integrated within the electronic health record (EHR) to provide real-time risk assessment without manual data entry. We present the first EHR-based machine learning model for GIB., Methods: The training cohort comprised 2546 patients and internal validation of 850 patients presenting with overt GIB (ie, hematemesis, melena, and hematochezia) to emergency departments of 2 hospitals from 2014 to 2019. External validation was performed on 926 patients presenting to a different hospital with the same EHR from 2014 to 2019. The primary outcome was a composite of red blood cell transfusion, hemostatic intervention (ie, endoscopic, interventional radiologic, or surgical), and 30-day all-cause mortality. We used structured data fields in the EHR, available within 4 hours of presentation, and compared the performance of machine learning models with current guideline-recommended risk scores, Glasgow-Blatchford Score, and Oakland Score. Primary analysis was area under the receiver operating characteristic curve. Secondary analysis was specificity at 99% sensitivity to assess the proportion of patients correctly identified as very low risk., Results: The machine learning model outperformed the Glasgow-Blatchford Score (area under the receiver operating characteristic curve, 0.92 vs 0.89; P < .001) and Oakland Score (area under the receiver operating characteristic curve, 0.92 vs 0.89; P < .001). At the very-low-risk threshold of 99% sensitivity, the machine learning model identified more very-low-risk patients: 37.9% vs 18.5% for Glasgow-Blatchford Score and 11.7% for Oakland Score (P < .001 for both comparisons)., Conclusions: An EHR-based machine learning model performs better than currently recommended clinical risk scores and identifies more very-low-risk patients eligible for discharge from the emergency department., (Copyright © 2024 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background: Despite advances in detection and treatments, biliary tract cancers continue to have poor survival outcomes. Currently, there is limited data investigating the significance of socioeconomic status, race/ethnicity, and environmental factors in biliary tract cancer survival., Aim: To investigate how socioeconomic status and race/ethnicity are associated with survival., Methods: Data from the Surveillance, Epidemiology, and End Results database for biliary and gallbladder adenocarcinomas were extracted from 1975 to 2016. Socioeconomic data included smoking, poverty level, education, adjusted household income, and percentage of foreign-born persons and urban population. Survival was calculated with Cox proportional hazards models for death in the 5-year period following diagnosis., Results: Our study included 15883 gallbladder, 11466 intrahepatic biliary, 12869 extrahepatic biliary and 7268 ampulla of Vater adenocarcinoma cases. When analyzing county-specific demographics, patients from counties with higher incomes were associated with higher survival rates [hazard ratio (HR) = 0.97, P <0.05]. Similarly, counties with a higher percentage of patients with a college level education and counties with a higher urban population had higher 5-year survival rates (HR = 0.96, P = 0.002 and HR = 0.97, P = 0.004, respectively)., Conclusion: Worse survival outcomes were observed in lower income counties while higher income and education level were associated with higher 5-year overall survival among gallbladder and biliary malignancies., Competing Interests: Conflict-of-interest statement: The authors have no conflicts of interest to disclose. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Recent epidemiologic studies of trends in gastrointestinal bleeding (GIB) provided results through 2014 or earlier and assessed only hospitalised patients, excluding patients presenting to emergency departments (EDs) who are not hospitalised., Aims: To provide the first U.S. nationwide epidemiological evaluation of all patients presenting to EDs with GIB METHODS: We used the Nationwide Emergency Department Sample for 2006-2019 to calculate yearly projected incidence of patients presenting to EDs with primary diagnoses of GIB, categorised by location and aetiology. Outcomes were assessed with multivariable analyses., Results: The age/sex-adjusted incidence for GIB increased from 378.4 to 397.5/100,000 population from 2006 to 2019. Upper gastrointestinal bleeding (UGIB) incidence decreased from 2006 to 2014 (112.3-94.4/100,000) before increasing to 116.2/100,000 by 2019. Lower gastrointestinal bleeding (LGIB) incidence increased from 2006 to 2015 (146.0 to 161.0/100,000) before declining to 150.2/100,000 by 2019. The proportion of cases with one or more comorbidities increased from 27.4% to 35.9% from 2006 to 2019. Multivariable analyses comparing 2019 to 2006 showed increases in ED discharges (odds ratio [OR] = 1.45; 95% confidence interval [CI] = 1.43-1.48) and decreases in red blood cell (RBC) transfusions (OR = 0.62; 0.61-0.63), endoscopies (OR = 0.60; 0.59-0.61), death (OR = 0.51; 0.48-0.54) and length of stay (relative ratio [RR] = 0.81; 0.80-0.82). Inpatient cost decreased from 2012 to 2019 (RR = 0.92; 0.91-0.93)., Conclusions: The incidence of GIB in the U.S. is increasing. UGIB incidence has been increasing since 2014 while LGIB incidence has been decreasing since 2015. Despite a more comorbid population in 2019, case fatality rate, length of stay and costs have decreased. More patients are discharged from the ED and the rate of RBC transfusions has decreased, possibly reflecting changing clinical practice in response to updated guidelines., (© 2022 John Wiley & Sons Ltd.)

Background: Oral cavity and oropharyngeal squamous cell cancers (OC-OPSCC) display high cancer-specific mortality and increased non-cancer mortality. We examined cause of death in patients treated for OC-OPSCC with brachytherapy, chemotherapy, external beam radiation, surgery, or combination of modalities. We hypothesized that brachytherapy does not increase non-cancer mortality comparably with external beam radiation., Methods: A database was constructed from institutional tumor registry and electronic medical record data from all patients with first OC-OPSCC diagnosis at our institution between 2000 and 2010, excluding patients with a second primary cancer at diagnosis. The primary outcome was association between treatment modality and non-cancer mortality., Results: Of 693 eligible patients, 460 were deceased; 84 from primary malignancy and 96 from a non-primary cancer cause, including 24 with a second primary cancer. 193 patients received brachytherapy. Cox proportional hazards regression was performed on treatment regimen, stratified by AJCC stage, race, and sex. Age, smoking history, and alcohol had HRs for death of 1.05 (p < 0.005), 1.37 (p = 0.106), and 2.24 (p < 0.005), respectively, while brachytherapy had a 0.53 HR (p < 0.005) for death. Non-smoking OPC patients had an 88% 5-year OS, suggesting these were largely HPV-driven cancers. In smoking OPC patients, 5-year OS was 61%. Non-cancer mortality HR of 0.36 for brachytherapy-treated patients., Conclusion: We report non-cancer mortality from a cohort of curatively treated OC-OPSCC and show a significant correlation between brachytherapy and non-cancer survival, independent of remission status. The impact of brachytherapy in OPC was strongest in smokers., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Upon addition of 5-15% PhNMe 2 H + X - (X = B(3,5-(CF 3 ) 2 C 6 H 3 ) 4 or B(C 6 F 5 ) 4 ) to Mo(NAr)(styrene)(OSiPh 3 ) 2 (Ar = N-2,6- i -Pr 2 C 6 H 3 ) in C 6 D 6 an equilibrium mixture of Mo(NAr)(styrene)(OSiPh 3 ) 2 and Mo(NAr)(CMePh)(OSiPh 3 ) 2 is formed over 36 h at 45 °C ( K eq = 0.36). A plausible intermediate in the interconversion of the styrene and 1-phenethylidene complexes is the 1-phenethyl cation, [Mo(NAr)(CHMePh)(OSiPh 3 ) 2 ] + , which can be generated using [(Et 2 H][B(C 2 H][B(C 6 F 5 ) 4 ] as the acid. The interconversion can be modeled as two equilibria involving protonation of Mo(NAr)(styrene)(OSiPh 3 ) 2 or Mo(NAr)(CMePh)(OSiPh 3 ) 2 and deprotonation of the α or β phenethyl carbon atom in [Mo(NAr)(CHMePh)(OSiPh 3 ) 2 ] + . The ratio of the rate of deprotonation of [Mo(NAr)(CHMePh)(OSiPh 3 ) 2 ] + by PhNMe 2 in the α position versus the β position is ∼10, or ∼30 per H β . The slow step is protonation of Mo(NAr)(styrene)(OSiPh 3 ) 2 ( k 1 = 0.158(4) L/(mol·min)). Proton sources such as (CF 3 ) 3 COH or Ph 3 SiOH do not catalyze the interconversion of Mo(NAr)(styrene)(OSiPh 3 ) 2 and Mo(NAr)(CMePh)(OSiPh 3 ) 2 , while the reaction of Mo(NAr)(styrene)(OSiPh 3 ) 2 with pyridinium salts generates only a trace (∼2%) of Mo(NAr)(CMePh)(OSiPh 3 ) 2 and forms a monopyridine adduct, [Mo(NAr)(CHMePh)(OSiPh 3 ) 2 (py)] + (two diastereomers). The structure of [Mo(NAr)(CHMePh)(OSiPh 3 ) 2 ] + has been confirmed in an X-ray study; there is no structural indication that a β proton is activated through a CH β interaction with the metal. W(NAr)(CMePh)(OSiPh 3 ) 2 is also converted into a mixture of W(NAr)(CMePh)(OSiPh 3 ) 2 and W(NAr)(styrene)(OSiPh 3 = 0.47 at 45 °C in favor of the styrene complex) with 10% [PhNMe 2 H][B(C K eq = 0.47 at 45 °C in favor of the styrene complex) with 10% [PhNMe 2 H][B(C 6 F 5 ) 4 ] as the catalyst; the time required to reach equilibrium is approximately the same as in the Mo system.

We report the first synthesis of aluminum hexafluorophosphate (Al(PF 6 ) 3 ) and its electrochemical properties in dimethyl sulfoxide (DMSO). The single crystal structure of the synthesized Al(PF 6 ) 3 is revealed as [Al(DMSO) 6 ](PF 6 ) 3 , and 0.25 M Al(PF 6 ) 3 in DMSO with high ionic conductivity is obtained. The purity of this electrolyte was further confirmed with nuclear magnetic resonance spectroscopy and electrospray ionization mass spectrometry. We then demonstrated the reversibility of Al deposition-stripping in this electrolyte using scanning electron microscopy and an X-ray photoelectron spectroscopy depth profiling study. The parasitic reaction involving DMSO decomposition during Al deposition is also identified via gas chromatography/electron ionization mass spectrometry.

Background and Aim: Guidelines recommend risk stratification scores in patients presenting with gastrointestinal bleeding (GIB), but such scores are uncommonly employed in practice. Automation and deployment of risk stratification scores in real time within electronic health records (EHRs) would overcome a major impediment. This requires an automated mechanism to accurately identify ("phenotype") patients with GIB at the time of presentation. The goal is to identify patients with acute GIB by developing and evaluating EHR-based phenotyping algorithms for emergency department (ED) patients., Methods: We specified criteria using structured data elements to create rules for identifying patients and also developed multiple natural language processing (NLP)-based approaches for automated phenotyping of patients, tested them with tenfold cross-validation for 10 iterations (n = 7144) and external validation (n = 2988) and compared them with a standard method to identify patient conditions, the Systematized Nomenclature of Medicine. The gold standard for GIB diagnosis was the independent dual manual review of medical records. The primary outcome was the positive predictive value., Results: A decision rule using GIB-specific terms from ED triage and ED review-of-systems assessment performed better than the Systematized Nomenclature of Medicine on internal validation and external validation (positive predictive value = 85% confidence interval:83%-87% vs 69% confidence interval:66%-72%; P < 0.001). The syntax-based NLP algorithm and Bidirectional Encoder Representation from Transformers neural network-based NLP algorithm had similar performance to the structured-data fields decision rule., Conclusions: An automated decision rule employing GIB-specific triage and review-of-systems terms can be used to trigger EHR-based deployment of risk stratification models to guide clinical decision making in real time for patients with acute GIB presenting to the ED., (© 2020 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Background: Pancytopenia, fever, and elevated D-dimer are significant clinical findings. The differential diagnosis includes hematological malignancies, severe coronavirus disease 2019 (COVID-19), tick-borne illnesses, and other etiologies., Case Presentation: We report the case of a 95-year-old woman who presented with high fever (103.6 °F), pancytopenia, and markedly elevated D-dimer (32.21 mg/L; reference range ≤ 0.95 mg/L) in late-autumn during the COVID-19 pandemic at a large academic institution. After remaining persistently febrile, a peripheral blood smear was ordered and revealed parasites consistent with Ehrlichia spp. Doxycycline monotherapy led to symptomatic improvement and resolution of her pancytopenia. During her hospital stay, a computed tomography angiogram of the chest revealed pulmonary emboli, and esophagogastroduodenoscopy uncovered arteriovenous malformations. After appropriate treatment, she was discharged on hospital day 7 and has since done well., Conclusions: Overall, our case offers a dramatic, unexpected presentation of ehrlichiosis in a nonagenarian. To our knowledge, this is the first report of concurrent ehrlichiosis and pulmonary embolus.

Vanadium-based catalysts have shown activity and selectivity in ring-opening metathesis polymerization of strained cyclic olefins comparable to those of Ru, Mo, and W catalysts. However, the application of V alkylidenes in routine organic synthesis is limited. Here, we present the first example of ring-closing olefin metathesis catalyzed by well-defined V chloride alkylidene phosphine complexes. The developed catalysts exhibit tolerance to various functional groups, such as an ether, an ester, a tertiary amide, a tertiary amine, and a sulfonamide. The size and electron-donating properties of the imido group and the phosphine play a crucial role in the stability of active intermediates. Reactions with ethylene and olefins suggest that both β-hydride elimination of the metallacyclobutene and bimolecular decomposition are responsible for catalyst degradation., (© 2020 Wiley-VCH GmbH.)

Objectives: Compression therapy is the mainstay of treatment for patients with venous ulcer disease. There exists a lack of certainty as to the safety of compression therapy in patients with congestive heart failure., Methods: A retrospective review of 95 patients with the diagnosis of congestive heart failure (systolic, diastolic, or combined), who underwent compression therapy at the wound care center of a large teaching hospital between January 2013 and June 2019, was performed. Patient outcomes including mortality, weight gain, admission for heart failure decompensation, and requirement for diuretic dose increase were compared to the general congestive heart failure population as well as to the registry data., Results: In the compression cohort, with a mean compression period of 310 days, seven patients (7.3%) were admitted for congestive heart failure exacerbation and six (6.3%) underwent diuretic dosage increase. Two patients (2.1%) died during the compression period. These endpoints were not significantly higher than within the general congestive heart failure population., Conclusions: Compression therapy appears safe amongst patients with stable congestive heart failure.

The novel coronavirus SARS-CoV-2 and resulting COVID-19 disease have had an unprecedented spread and continue to cause an increasing number of fatalities worldwide. While vaccines are still under development, social distancing, extensive testing, and quarantining of confirmed infected subjects remain the most effective measures to contain the pandemic. These measures carry a significant socioeconomic cost. In this work, we introduce a novel optimization-based decision-making framework for managing the COVID-19 outbreak in the US. This includes modeling the dynamics of affected populations, estimating the model parameters and hidden states from data, and an optimal control strategy for sequencing social distancing and testing events such that the number of infections is minimized. The analysis of our extensive computational efforts reveals that social distancing and quarantining are most effective when implemented early, with quarantining of confirmed infected subjects having a much higher impact. Further, we find that "on-off" policies alternating between strict social distancing and relaxing such restrictions can be effective at "flattening" the curve while likely minimizing social and economic cost.

Background: Critical limb ischemia (CLI) is the clinical manifestation of severe peripheral artery disease presenting as rest pain (RP) and tissue loss (TL). Most studies compare CLI as a homogenous group with claudication with limited database studies specifically studying these differences. We hypothesize that CLI should be stratified into RP and TL because of significant differences in disease severity, comorbidities, and outcomes., Methods: The American College of Surgeons National Surgical Quality Improvement Program database from 2012 to 2016 was reviewed. All patients with a postoperative diagnosis of CLI undergoing femoral to popliteal bypass (FPB) with vein or graft were identified. Patients were stratified into cohorts based on International Classification of Disease (ICD)-9 or ICD-10 codes for RP or TL (gangrene or ulcer). Univariate and multivariate analyses were performed to examine 30-day mortality, morbidity, major amputation, and readmission adjusting for demographics, comorbidities, and procedural details., Results: There were 5,304 patients. Compared to RP, patients with TL were older (P < 0.0001) and more likely to be dependent (P < 0.0001). TL patients were also more likely to have diabetes (P < 0.0001), congestive heart failure (P < 0.0001), renal failure (P = 0.004), dialysis (P < 0.0001), history of wound infection (P < 0.0001), and sepsis (P < 0.0001). TL patients had higher American Society of Anesthesiologists class (P < 0.0001), were less likely to be transferred from home (P < 0.0001), and more likely to receive an FPB with vein (P = 0.03). Patients with TL had worse perioperative outcomes compared with RP in terms of pneumonia (P = 0.004), unplanned intubation (P = 0.009), cardiac arrest requiring cardiopulmonary resuscitation (P = 0.003), bleeding requiring transfusions (P < 0.0001), sepsis (P < 0.0001), septic shock (P = 0.02), and reoperation (P < 0.0001). TL was associated with significantly higher 30-day morbidity (P < 0.0001), 30-day mortality (P < 0.0001), major amputation (P = 0.0004), and readmission rates (P = 0.005). Patients with TL compared with those with RP also had longer hospital stays (P < 0.0001) and days between operation to discharge (P < 0.0001). TL was independently associated with increased 30-day morbidity (OR: 1.16 [1.00-1.35]) and major amputation (OR: 2.48 [1.29-4.76]) compared with RP., Conclusions: Patients with RP and TL have drastic differences that impact perioperative mortality and readmissions. TL is an independent predictor of 30-day morbidity and major amputation. The stratification of CLI into RP and TL can provide insight into variations in outcomes and provide a means to quantify the risks associated with the 2 manifestations of the disease., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background & Aims: Guidelines recommend colonoscopy evaluation within 24 hours of presentation or admission in patients with high-risk or severe acute lower gastrointestinal bleeding (LGIB). Meta-analyses of the timing of colonoscopy have relied primarily on observational studies that had major potential for bias. We performed a systematic review of randomized trials to determine optimal timing of colonoscopy for patients hospitalized with acute LGIB., Methods: We searched publication databases through July 2019 and abstracts from gastroenterology meetings through November 2019 for randomized trials of patients with acute LGIB or hematochezia. We searched for studies that compared early colonoscopy (within 24 hours) with elective colonoscopy beyond 24 hours and/or other diagnostic tests. Our primary outcome was further bleeding, defined as persistent or recurrent bleeding after index examination. Secondary outcomes included mortality, diagnostic yield (identifying source of bleeding), endoscopic intervention, and any primary hemostatic intervention (endoscopic, surgical, or interventional radiologic). We performed dual independent review, data extraction, and risk of bias assessments. We performed the meta-analysis using a random-effects model., Results: Our final analysis included data from 4 randomized trials. Further bleeding was not decreased among patients who received early vs later, elective colonoscopy (relative risk [RR] for further bleeding with early colonoscopy, 1.57; 95% CI. 0.74-3.31). We did not find significant differences in the secondary outcomes of mortality (RR, 0.93; 95% CI, 0.05-17.21), diagnostic yield (RR, 1.09; 95% CI, 0.99-1.21), endoscopic intervention (RR, 1.53; 95% CI, 0.67-3.48), or any primary hemostatic intervention (RR, 1.33; 95% CI, 0.92-1.92)., Conclusions: In a meta-analysis of randomized trials, we found that colonoscopy within 24 hours does not reduce further bleeding or mortality in patients hospitalized with acute LGIB. Based on these findings, patients hospitalized with acute LGIB do not generally require early colonoscopy., (Copyright © 2020 AGA Institute. Published by Elsevier Inc. All rights reserved.)

We review the impact of control systems and strategies on the energy efficiency of chemical processes. We show that, in many ways, good control performance is a necessary but not sufficient condition for energy efficiency. The direct effect of process control on energy efficiency is manyfold: Reducing output variability allows for operating chemical plants closer to their limits, where the energy/economic optima typically lie. Further, good control enables novel, transient operating strategies, such as conversion smoothing and demand response. Indirectly, control systems are key to the implementation and operation of more energy-efficient plant designs, as dictated by the process integration and intensification paradigms. These conclusions are supported with references to numerous examples from the literature.

We demonstrate a strongly thresholded response in cyclotrimethylene trinitramine (RDX) when it is cylindrically shocked using a novel waveguide geometry. Using ultrafast single-shot multi-frame imaging, we demonstrate that <100 μm diameter single crystals of RDX embedded in a polymer host deform along preferential planes for >100 ns after the shock first arrives in the crystal. We use in situ imaging and time-resolved photoemission to demonstrate that short-lived chemistry occurs with complex deformation pathways. Using scanning electron microscopy and ultra-small-angle X-ray scattering, we demonstrate that the shock-induced dynamics leave behind porous crystals, with pore shapes and sizes that change significantly with shock pressure. A threshold pressure of ∼12 GPa at the center of convergence separated the single-mode planar crystal deformations from the chemistry-coupled multi-plane dynamics at higher pressures. Our observations indicate preferential directions for deformation in our cylindrically shocked system, despite the applied stress along many different crystallographic planes.