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Energy systems optimization problems are complex due to strongly non-linear system behavior and multiple competing objectives, e.g. economic gain vs. environmental impact. Moreover, a large number of input variables and different variable types, e.g. continuous and categorical, are challenges commonly present in real-world applications. In some cases, proposed optimal solutions need to obey explicit input constraints related to physical properties or safety-critical operating conditions. This paper proposes a novel data-driven strategy using tree ensembles for constrained multi-objective optimization of black-box problems with heterogeneous variable spaces for which underlying system dynamics are either too complex to model or unknown. In an extensive case study comprised of synthetic benchmarks and relevant energy applications we demonstrate the competitive performance and sampling efficiency of the proposed algorithm compared to other state-of-the-art tools, making it a useful all-in-one solution for real-world applications with limited evaluation budgets., Comment: 36 pages, 8 figures, 5 tables

Gradient boosted trees and other regression tree models are known to perform well in a wide range of real-world, industrial applications. These tree models (i) offer insight into important prediction features, (ii) effectively manage sparse data, and (iii) have excellent prediction capabilities. We consider holistic decision-making problems where pre-trained tree models are part of larger optimization tasks. Our contributions include: (i) explicitly integrating model uncertainty considerations, (ii) solving the larger optimization problems that incorporate these uncertain tree models, (iii) proving that the resulting solutions are globally optimal, i.e., no better solution exists.

Gradient boosted trees and other regression tree models perform well in a wide range of real-world, industrial applications. These tree models (i) offer insight into important prediction features, (ii) effectively manage sparse data, and (iii) have excellent prediction capabilities. Despite their advantages, they are generally unpopular for decision-making tasks and black-box optimization, which is due to their difficult-to optimize structure and the lack of a reliable uncertainty measure. ENTMOOT is our new framework for integrating (already trained) tree models into larger optimization problems. The contributions of ENTMOOT include: (i) explicitly introducing a reliable uncertainty measure that is compatible with tree models, (ii) solving the larger optimization problems that incorporate these uncertainty aware tree models, (iii) proving that the solutions are globally optimal, i.e. no better solution exists. In particular, we show how the ENTMOOT approach allows a simple integration of tree models into decision-making and black-box optimization, where it proves as a strong competitor to commonly-used frameworks., Comment: 33 pages, 10 figures, 2 tables

Decision trees usefully represent sparse, high-dimensional, and noisy data. Having learned a function from these data, we may want to thereafter integrate the function into a larger decision-making problem, for example, for picking the best chemical process catalyst. We study a large-scale, industrially relevant mixed-integer nonlinear nonconvex optimization problem involving both gradient-boosted trees and penalty functions mitigating risk. This mixed-integer optimization problem with convex penalty terms broadly applies to optimizing pretrained regression tree models. Decision makers may wish to optimize discrete models to repurpose legacy predictive models or they may wish to optimize a discrete model that accurately represents a data set. We develop several heuristic methods to find feasible solutions and an exact branch-and-bound algorithm leveraging structural properties of the gradient-boosted trees and penalty functions. We computationally test our methods on a concrete mixture design instance and a chemical catalysis industrial instance.

For many austerity-hit Western countries, the defence budget has been a prime target for significant cuts. Nowhere has this been more apparent than in the United States. Yet one element of the Pentagon's budget continues to grow: cyber. High-profile security breaches at the corporate level and reports of cyber-espionage at the national level seemingly justify the vast sums involved in ensuring cyber-security. However, Robert M Lee and Thomas Rid argue that ‘cyber-angst’ is damaging – and self-serving. In this article, they list thirteen reasons why such cyber-security hype is counterproductive.

Background & Aims: Apobec-1 is an RNA-specific cytidine deaminase whose forced overexpression in transgenic animals is associated with hepatic carcinogenesis. Apobec-1 messenger RNA (mRNA) undergoes alternative splicing, generating a catalytically inactive peptide, apobec-T. We have examined apobec-1 gene expression in human gastrointestinal tumors and in colon cancer–derived cell lines. Methods: Levels of the full-length (apobec-1) and alternatively spliced (apobec-T) mRNAs were measured by RNase protection assay, and apobec-T distribution was determined by immunocytochemical localization. Results: Apobec-1 mRNA was detectable in normal and colon cancer tissue, metastatic nodules, and certain colon cancer–derived cell lines. Apobec-T mRNA abundance was increased an average of 3.5-fold in colon cancers compared with paired control tissue (range, 0.5–14-fold). Immunocytochemical analysis showed apobec-T expression in normal fetal and adult colon and in gastric and small intestinal adenocarcinomas, colonic tubular adenomas, and both primary and metastatic colonic tumors. Overexpression of apobec-T in a tetracycline-responsive cell line decreased cellular proliferation. Conclusions: Apobec-T is expressed in normal, adenomatous, and cancerous gastrointestinal tissues, and levels of the mRNA encoding this peptide are significantly increased in colon cancer. Although its relationship to colon carcinogenesis has not been defined, the regulated overexpression of apobec-T is associated with an altered growth phenotype. GASTROENTEROLOGY 1998;115:1096-1103

C--U RNA editing of neurofibromatosis 1 (NF1) mRNA changes an arginine (CGA) to a UGA translational stop codon, predicted to result in translational termination of the edited mRNA. Previous studies demonstrated varying degrees of C--U RNA editing in peripheral nerve-sheath tumor samples (PNSTs) from patients with NF1, but the basis for this heterogeneity was unexplained. In addition, the role, if any, of apobec-1, the catalytic deaminase that mediates C--U editing of mammalian apolipoprotein B (apoB) RNA, was unresolved. We have examined these questions in PNSTs from patients with NF1 and demonstrate that a subset (8/34) manifest C--U editing of RNA. Two distinguishing characteristics were found in the PNSTs that demonstrated editing of NF1 RNA. First, these tumors express apobec-1 mRNA, the first demonstration, in humans, of its expression beyond the luminal gastrointestinal tract. Second, PNSTs with C--U editing of RNA manifest increased proportions of an alternatively spliced exon, 23A, downstream of the edited base. C--U editing of RNA in these PNSTs was observed preferentially in transcripts containing exon 23A. These findings were complemented by in vitro studies using synthetic RNA templates incubated in the presence of recombinant apobec-1, which again confirmed preferential editing of transcripts containing exon 23A. Finally, adenovirus-mediated transfection of HepG2 cells revealed induction of editing of apoB RNA, along with preferential editing of NF1 transcripts containing exon 23A. Taken together, the data support the hypothesis that C--U RNA editing of the NF1 transcript occurs both in a subset of PNSTs and in an alternatively spliced form containing a downstream exon, presumably an optimal configuration for enzymatic deamination by apobec-1.

The aim of these studies was to characterize the synthesis and secretion of lipoproteins and apolipoprotein B (apo B) and apo A-I by a newborn swine intestinal epithelial cell line (IPEC-1). Differentiated cells exhibited enterocytic features, including microvilli. [3H] oleic acid was taken up and incorporated into cellular lipids and secreted into the basolateral medium in lipoproteins. Total apo B and apo A-I secreted increased with oleic acid incubation. However, cellular apo B and apo A-I content did not change. Whereas undifferentiated cells synthesized and secreted only apo B-100, both apo B-100 and apo B-48 were produced by differentiated cells. The ratio of radiolabeled apo B-48 to apo B-100 in both basolateral medium and cell homogenate increased with oleic acid treatment after 24-h steady-state labeling. However, apo B mRNA editing was unchanged, indicating posttranslational regulation of this ratio. Pulse-chase radiolabeling demonstrated no major changes in cellular or basolateral medium apolipoprotein labeling kinetics with oleic acid or dexamethasone incubation. The dissociation of apo B and apo A-I mass secretion from the secretion of radiolabeled apo B and apo A-I in response to oleic acid absorption suggests the presence of an intracellular pool of apolipoprotein with a slow turnover that is mobilized for secretion in response to fatty acid uptake.

Purpose We studied patients who had mottled cyan-colored opacities of the cornea to better understand the cause and prognosis of this entity. Methods We reviewed examinations of patients who had a mottled cyan opacification of the cornea. Risk factors, including contact lens wear and exposure to heavy metals, were analyzed. Clinical findings, pachymetry specular microscopy, and progression of the abnormality were noted. Results Six patients who had a mottled cyan opacification at the level of Descemet's membrane were identified. These opacities were located in the peripheral and midperipheral cornea. All patients had bilateral findings, had visual acuities of 20/20 or better, and were asymptomatic. All patients had worn soft contact lenses bilaterally for periods ranging from seven to 14 years. Conclusion All patients had the similar clinical appearance of a mottled cyan opacification at the level of Descemet's membrane in the peripheral cornea. Long-term contact lens wear appears to be associated; however, the exact cause is unclear.

Since the late 1970's flow cytometry has been accepted as a fast and accurate technique for the quantification of nuclear DNA content (Deaven 1982). However, use of the technology has typically been confined to clinical settings due to the high cost of the instrumentation and the requirement for trained personnel. Flow cytometry recently has been applied to the study of genetic damage in wild populations. McBee and Bickham (1988) detected DNA damage in wild rodents inhabiting a dumpsite contaminated with petrochemicals, and Bickham et al. (1988) detected DNA aneuploidy in turtles found in seepage basins contaminated with radiation. Given these few studies, there is a need to establish a data base for the application of flow cytometry to environmental screening.

The use of computer graphics equipment to draw sound tracks directly on film is discussed. This method of recording enables the computer user to add sound to his movies using equipment and techniques with which he is familiar. It introduces problems from two sources, the incremental movement of the film and the detailed control over the recorded wave shapes that must be exercised by the programmer. Examples of some of these problems, with suggested solutions, are given.

Vibration waveforms are taken at several points on a vibrating surface and then combined, using a computer with a cathode‐ray‐tube display, to produce several representations of the movement of the surface. An important advantage of this method is that the forms of the data and representations lend themselves readily to manipulation by the computer. A noncontact vibration pickup, developed especially for this application, is briefly described.

DNA from 10T1/2 cells transformed by activated neutrophils was analyzed for restriction length polymorphisms (RFLPs) in cellular homologues of retroviral oncogenes, and consistent RFLPs were found in MspI sites of the c-abl gene of all PMN-transformed cell lines. MspI digests probed with c-myc, v-Ki-ras, v-Ha-ras or v-mos showed no RFLPs, and none were observed in EcoRI, PstI, HindIII, BamHI, SmaI, Sau3a, MboI, HhaI, or TaqI digests probed with v-abl. Analysis of HpaII digests supports the conclusion that c-abl RFLPs result from differential methylation of the CCGG HpaII/MspI recognition sequence. MspI RFLPs in the c-abl gene may provide markers for oxidant-related genetic injury.

A 10-year review of 101 patients sustaining an early postoperative small bowel obstruction within 30 days of celiotomy was carried out. Signs, symptoms, lab tests, and x-rays did not indicate which patients required operation. Twenty-three patients were operated on for either failure to resolve their obstruction or because it was feared that ischemic bowel was present. In none of these patients, nor the 78 patients who resolved without reoperation, did dead bowel occur. Early postoperative small bowel obstruction was most often due to adhesions and inflammatory processes. Seven patients died (6.9%), three in the operated and four in the nonoperated group. Because ischemic bowel is very unlikely in patients with early postoperative small bowel obstruction, we advise 10 to 14 days of nasogastric suction initially; after this, improvement is unlikely without reoperation.