Measuring the Effects of Federal Budget Dysfunction: Impacts of Continuing Resolutions on Public Procurement

Excerpt from the Proceedings of the Nineteenth Annual Acquisition Research SymposiumThis study measures the behavioral effects of continuing resolutions by examining their impact on federal procurement activities. The restrictions imposed by continuing resolutions are explored as an example of political control over a public organization. The analysis employs a dataset describing the timing of U.S. Marine Corps purchase orders for goods and services. Individual purchase orders were sampled over a four-year period (2016−2019) that endured continuing resolutions of different lengths. The analysis examines the impact of continuing resolutions on the number of purchase orders initiated, the duration of their review period, and the dollar amount per request. The results depict multiple impacts that appear to concentrate on requests for services rather than commodities. These findings help quantify the magnitude of the disruptions caused by federal budgetary dysfunction.Approved for public release; distribution is unlimited

Calibration Model Maintenance in Melamine Resin Production: Integrating Drift Detection, Smart Sample Selection and Model Adaptation

The physico-chemical properties of Melamine Formaldehyde (MF) based thermosets are largely influenced by the degree of polymerization (DP) in the underlying resin. On-line supervision of the turbidity point by means of vibrational spectroscopy has recently emerged as a promising technique to monitor the DP of MF resins. However, spectroscopic determination of the DP relies on chemometric models, which are usually sensitive to drifts caused by instrumental and/or sample associated changes occurring over time. In order to detect the time point when drifts start causing prediction bias, we here explore a universal drift detector based on a faded version of the Page-Hinkley (PH) statistic, which we test in three data streams from an industrial MF resin production process. We employ committee disagreement (CD), computed as the variance of model predictions from an ensemble of partial least squares (PLS) models, as a measure for sample-wise prediction uncertainty and use the PH statistic to detect hanges in this quantity. We further explore supervised and unsupervised strategies for (semi-)automatic model adaptation upon detection of a drift. For the former, manual reference measurements are requested whenever statistical thresholds on Hotelling’s $T^2$ and/or Q-Residuals are violated. Models are subsequently re-calibrated using weighted partial least squares in order to increase the influence of newer samples, which increases the flexibility when adapting to new (drifted) states. Unsupervised model adaptation is carried out exploiting the dual antecedent-consequent structure of a recently developed fuzzy systems variant of PLS termed FLEXFIS-PLS. In particular, antecedent parts are updated while maintaining the internal structure of the local linear predictors (i.e. the consequents). We found improved drift detection capability of the CD compared to Hotelling’s $T^2$ and Q-Residuals when used in combination with the proposed PH test. Furthermore, we found that active selection of samples by active learning (AL) used for subsequent model adaptation is advantageous compared to passive (random) selection in case that a drift leads to persistent prediction bias allowing more rapid adaptation at lower reference measurement rates. Fully unsupervised adaptation using FLEXFIS-PLS could improve predictive accuracy significantly for light drifts but was not able to fully compensate for prediction bias in case of significant lack of fit w.r.t. the latent variable space

Primary peritoneal mesothelioma: A rare cause of malignant ascites

Abstract Introduction: The evaluation of peritoneal masses requires a focused, systematic approach. While peritoneal fluid analysis and axial imaging are essential to the workup, further analysis is often needed for a final diagnosis. We present a case of primary peritoneal mesothelioma mimicking peritoneal carcinomatosis of gastrointestinal origin on computerized tomography (CT) imaging. Case presentation: A 61-year-old man presented to the hospital with an approximate 1-month history of abdominal distention, dyspnea, nausea and fatigue. Peritoneal studies revealed serum-ascites-albumin-gradient (SAAG) of less than 1.1, consistent with non-portal hypertension ascites. CT abdomen revealed large-volume ascites with omental caking, concerning for peritoneal carcinomatosis. Peritoneal fluid cytology was initially inconclusive, prompting ultrasound-guided peritoneal biopsies, which revealed primary abdominal mesothelioma. Conclusions: Neither CT nor peritoneal cytology are typically sufficient for the diagnosis of peritoneal mesothelioma. When strong clinical suspicion exists, early tissue biopsies should be pursued

Comparison of the in Vitro Uptake and Toxicity of Collagen- and Synthetic Polymer-Coated Gold Nanoparticles

We studied the physico-chemical properties (size, shape, zeta-potential),cellular internalization and toxicity of gold nanoparticles (NPs) stabilized with the most abundant mammalian protein, collagen. The properties of these gold NPs were compared to the same sized gold NPs coated with synthetic poly(isobutylene-alt-maleic anhydride) (PMA). Intracellular uptake and cytotoxicity were assessed in two cell lines (cervical carcinoma and lung adenocarcinoma cells) by employing inductively-coupled plasma-mass spectrometry (ICP-MS) analysis and a cell viability assay based on 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT),respectively. We found that the collagen-coated gold NPs exhibit lower cytotoxicity, but higher uptake levels than PMA-coated gold NPs. These results demonstrate that the surface coating of Au NPs plays a decisive role in their biocompatibility

Учет и анализ движения основных средств на нефтегазодобывающем предприятии

Учет и анализ движения основных средств на предприятии. В работе рассматриваются понятие основных средств, их классификация, документооборот, первичные документы по основным средствам и правильное их заполнение.Accounting and analysis of the movement of fixed assets in the enterprise. The paper discusses the concept of fixed assets, their classification, document flow, primary documents on fixed assets and their correct filling

The Confidence Database

Understanding how people rate their confidence is critical for the characterization of a wide range of perceptual, memory, motor and cognitive processes. To enable the continued exploration of these processes, we created a large database of confidence studies spanning a broad set of paradigms, participant populations and fields of study. The data from each study are structured in a common, easy-to-use format that can be easily imported and analysed using multiple software packages. Each dataset is accompanied by an explanation regarding the nature of the collected data. At the time of publication, the Confidence Database (which is available at https://osf.io/s46pr/) contained 145 datasets with data from more than 8,700 participants and almost 4 million trials. The database will remain open for new submissions indefinitely and is expected to continue to grow. Here we show the usefulness of this large collection of datasets in four different analyses that provide precise estimations of several foundational confidence-related effects

The role of intracellular trafficking of CdSe/ZnS QDs on their consequent toxicity profile

Nanoparticle interactions with cellular membranes and the kinetics of their transport and localization are important determinants of their functionality and their biological consequences. Understanding these phenomena is fundamental for the translation of such NPs from in vitro to in vivo systems for bioimaging and medical applications. Two CdSe/ZnS quantum dots (QD) with differing surface functionality (NH2 or COOH moieties) were used here for investigating the intracellular uptake and transport kinetics of these QDs.status: publishe