Reduction of manifolds with semi-negative holomorphic sectional curvature

In this note, we continue the investigation of a projective K\"ahler manifold $M$ of semi-negative holomorphic sectional curvature $H$. We introduce a new differential geometric numerical rank invariant which measures the number of linearly independent {\it truly flat} directions of $H$ in the tangent spaces. We prove that this invariant is bounded above by the nef dimension and bounded below by the numerical Kodaira dimension of $M$. We also prove a splitting theorem for $M$ in terms of the nef dimension and, under some additional hypotheses, in terms of the new rank invariant

Low Cost Attitude Sensors for Spacecraft

A short overview is presented on low cost attitude sensors developed by Applied Research Corporation. More or less existing technology has been used, but major emphasis was directed to considerably reduce the cost of these units without compromising their quality and reliability. Horizon and sun aspect sensors have been developed and manufactured. They were successfully flown on the space shuttle Atlantis (STS 34, October 18, 1989). We have further manufactured 10 horizon sensors and 15 sun aspect sensors and delivered them to Goddard (Wallops) Space Flight Center for future use on sounding rockets. The angular errors are about ±0.1 to 0.2 for the horizon and sun aspect sensors. Their mass is about 0.3 to 0.8 kg and their power requirement about 0.1 to 1.5 W. We have recently won a contract with Goddard to develop a low cost star tracker with an angular error of about ±5 sec of arc. Our plan is to produce a protoflight unit of such a sensor in about 24 months. Some details of the results obtained from the shuttle flight and some system details will be presented

Sign-Rank Can Increase Under Intersection

The communication class UPP^{cc} is a communication analog of the Turing Machine complexity class PP. It is characterized by a matrix-analytic complexity measure called sign-rank (also called dimension complexity), and is essentially the most powerful communication class against which we know how to prove lower bounds. For a communication problem f, let f wedge f denote the function that evaluates f on two disjoint inputs and outputs the AND of the results. We exhibit a communication problem f with UPP^{cc}(f)= O(log n), and UPP^{cc}(f wedge f) = Theta(log^2 n). This is the first result showing that UPP communication complexity can increase by more than a constant factor under intersection. We view this as a first step toward showing that UPP^{cc}, the class of problems with polylogarithmic-cost UPP communication protocols, is not closed under intersection. Our result shows that the function class consisting of intersections of two majorities on n bits has dimension complexity n^{Omega(log n)}. This matches an upper bound of (Klivans, O\u27Donnell, and Servedio, FOCS 2002), who used it to give a quasipolynomial time algorithm for PAC learning intersections of polylogarithmically many majorities. Hence, fundamentally new techniques will be needed to learn this class of functions in polynomial time

Exploratory Analysis of Highly Heterogeneous Document Collections

We present an effective multifaceted system for exploratory analysis of highly heterogeneous document collections. Our system is based on intelligently tagging individual documents in a purely automated fashion and exploiting these tags in a powerful faceted browsing framework. Tagging strategies employed include both unsupervised and supervised approaches based on machine learning and natural language processing. As one of our key tagging strategies, we introduce the KERA algorithm (Keyword Extraction for Reports and Articles). KERA extracts topic-representative terms from individual documents in a purely unsupervised fashion and is revealed to be significantly more effective than state-of-the-art methods. Finally, we evaluate our system in its ability to help users locate documents pertaining to military critical technologies buried deep in a large heterogeneous sea of information.Comment: 9 pages; KDD 2013: 19th ACM SIGKDD Conference on Knowledge Discovery and Data Minin

ІНФОРМАЦІЙНІ ТЕХНОЛОГІЇ ПРОСТОРОВОЇ ІНВЕНТАРИЗАЦІЇ ПАРНИКОВИХ ГАЗІВ У ЕНЕРГЕТИЧНОМУ СЕКТОРІ СІЛЕЗЬКОГО ВОЄВОДСТВА

GIS technology of spatial inventory of greenhouse gases (carbon dioxide, methane, etc.) in the energy sector of Silesia Region in Poland has been presented. Georeferenced databases, GIS software, and international inventory methodologies have been used. The mathematical models for inventory of carbon dioxide, methane and other greenhouse gases during the combustion of fuel in the production of electricity, in the residential sector, industry, construction, and transport have beencreated. These models allow to obtain the spatial distribution of total emissions of greenhouse gases of Silesia Region, taking into account the contribution of each region in the overall processes of emission.Представлено геоінформаційні технології просторової інвентаризації парникових газів (двоокису вуглецю, метану та ін.) в енергетичному секторі в Сілезькому воєводстві Польщі. Використано георозподілені бази даних, програмне забезпечення геоінформаційної системи та міжнародні методології інвентаризації. Розроблено математичні моделі для інвентаризації двоокису вуглецю, метану та інших парникових газів в процесі спалювання палива на виробництво електроенергії, в житловому секторі, у промисловості та будівництві, на транспорті. Ці моделі дали змогу отримати просторовий розподіл сумарних викидів парникових газів Сілезького воєводства з врахуванням внеску кожного району в загальні процеси емісії

Generation of structurally novel short carotenoids and study of their biological activity

Recent research interest in phytochemicals has consistently driven the efforts in the metabolic engineering field toward microbial production of various carotenoids. In spite of systematic studies, the possibility of using C(30) carotenoids as biologically functional compounds has not been explored thus far. Here, we generated 13 novel structures of C(30) carotenoids and one C(35) carotenoid, including acyclic, monocyclic, and bicyclic structures, through directed evolution and combinatorial biosynthesis, in Escherichia coli. Measurement of radical scavenging activity of various C(30) carotenoid structures revealed that acyclic C(30) carotenoids showed higher radical scavenging activity than did DL-α-tocopherol. We could assume high potential biological activity of the novel structures of C(30) carotenoids as well, based on the neuronal differentiation activity observed for the monocyclic C(30) carotenoid 4,4′-diapotorulene on rat bone marrow mesenchymal stem cells. Our results demonstrate that a series of structurally novel carotenoids possessing biologically beneficial properties can be synthesized in E. coli

Comparative analysis of the human serine hydrolase OVCA2 to the model serine hydrolase homolog FSH1 from S. cerevisiae

Over 100 metabolic serine hydrolases are present in humans with confirmed functions in metabolism, immune response, and neurotransmission. Among potentially clinically relevant but uncharacterized human serine hydrolases is OVCA2, a serine hydrolase that has been linked with a variety of cancer-related processes. Herein, we developed a heterologous expression system for OVCA2 and determined the comprehensive substrate specificity of OVCA2 against two ester substrate libraries. Based on this analysis, OVCA2 was confirmed as a serine hydrolase with a strong preference for long-chain alkyl ester substrates (\u3e10-carbons) and high selectivity against a variety of short, branched, and substituted esters. Substitutional analysis was used to identify the catalytic residues of OVCA2 with a Ser117-His206-Asp179 classic catalytic triad. Comparison of the substrate specificity of OVCA2 to the model homologue FSH1 from Saccharomyces cerevisiae illustrated the tighter substrate selectivity of OVCA2, but their overlapping substrate preference for extended straight-chain alkyl esters. Conformation of the overlapping biochemical properties of OVCA2 and FSH1 was used to model structural information about OVCA2. Together our analysis provides detailed substrate specificity information about a previously, uncharacterized human serine hydrolase and begins to define the biological properties of OVCA2

An equivalence between private classification and online prediction

https://arxiv.org/pdf/2003.00563.pd