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Osteosarcoma is the most common primary bone cancer whose standard treatment includes pre-operative chemotherapy followed by resection. Chemotherapy response is used for predicting prognosis and further management of patients. Necrosis is routinely assessed post-chemotherapy from histology slides on resection specimens where necrosis ratio is defined as the ratio of necrotic tumor to overall tumor. Patients with necrosis ratio >=90% are known to have better outcome. Manual microscopic review of necrosis ratio from multiple glass slides is semi-quantitative and can have intra- and inter-observer variability. We propose an objective and reproducible deep learning-based approach to estimate necrosis ratio with outcome prediction from scanned hematoxylin and eosin whole slide images. We collected 103 osteosarcoma cases with 3134 WSIs to train our deep learning model, to validate necrosis ratio assessment, and to evaluate outcome prediction. We trained Deep Multi-Magnification Network to segment multiple tissue subtypes including viable tumor and necrotic tumor in pixel-level and to calculate case-level necrosis ratio from multiple WSIs. We showed necrosis ratio estimated by our segmentation model highly correlates with necrosis ratio from pathology reports manually assessed by experts where mean absolute differences for Grades IV (100%), III (>=90%), and II (>=50% and <90%) necrosis response are 4.4%, 4.5%, and 17.8%, respectively. We successfully stratified patients to predict overall survival with p=10^-6 and progression-free survival with p=0.012. Our reproducible approach without variability enabled us to tune cutoff thresholds, specifically for our model and our data set, to 80% for OS and 60% for PFS. Our study indicates deep learning can support pathologists as an objective tool to analyze osteosarcoma from histology for assessing treatment response and predicting patient outcome.

For integers $n>2$ and $k>0$, an $(n\times n)/k$ semi-Latin square is an $n\times n$ array of $k$-subsets (called blocks) of an $nk$-set (of treatments), such that each treatment occurs once in each row and once in each column of the array. A semi-Latin square is uniform if every pair of blocks, not in the same row or column, intersect in the same positive number of treatments. We show that when a uniform $(n\times n)/k$ semi-Latin square exists, the Schur optimal $(n\times n)/k$ semi-Latin squares are precisely the uniform ones. We then compare uniform semi-Latin squares using the criterion of pairwise-variance (PV) aberration, introduced by J.P. Morgan for affine resolvable designs, and determine the uniform $(n\times n)/k$ semi-Latin squares with minimum PV aberration when there exist $n-1$ mutually orthogonal Latin squares (MOLS) of order $n$. These do not exist when $n=6$, and the smallest uniform semi-Latin squares in this case have size $(6\times 6)/10$. We present a complete classification of the uniform $(6\times 6)/10$ semi-Latin squares, and display the one with least PV aberration. We give a construction producing a uniform $((n+1)\times (n+1))/((n-2)n)$ semi-Latin square when there exist $n-1$ MOLS of order $n$, and determine the PV aberration of such a uniform semi-Latin square. Finally, we describe how certain affine resolvable designs and balanced incomplete-block designs (BIBDs) can be constructed from uniform semi-Latin squares. From the uniform $(6\times 6)/10$ semi-Latin squares we classified, we obtain (up to block design isomorphism) exactly 16875 affine resolvable designs for 72 treatments in 36 blocks of size 12 and 8615 BIBDs for 36 treatments in 84 blocks of size 6. In particular, this shows that there are at least 16875 pairwise non-isomorphic orthogonal arrays $\mathrm{OA}(72,6,6,2)$., Comment: 21 pages; accepted manuscript

We determine that there is no partial geometry ${\cal G}$ with parameters $(s,t,\alpha)=(4,27,2)$. The existence of such a geometry has been a challenging open problem of interest to researchers for almost 40 years. The particular interest in ${\cal G}$ is due to the fact that it would have the exceptional McLaughlin graph as its point graph. Our proof makes extensive use of symmetry and high-performance distributed computing, and details of our techniques and checks are provided. One outcome of our work is to show that a pseudogeometric strongly regular graph achieving equality in the Krein bound need not be the point graph of any partial geometry., Comment: 19 pages

We determine new upper bounds for the clique numbers of strongly regular graphs in terms of their parameters. These bounds improve on the Delsarte bound for infinitely many feasible parameter tuples for strongly regular graphs, including infinitely many parameter tuples that correspond to Paley graphs., Comment: 13 pages

It is known that, up to isomorphism, there is a unique distance-regular graph $\Delta$ with intersection array {32,27;1,12} (equivalently, $\Delta$ is the unique strongly regular graph with parameters (105,32,4,12)). Here we investigate the distance-regular antipodal covers of $\Delta$. We show that, up to isomorphism, there is just one distance-regular antipodal triple cover of $\Delta$ (a graph $\hat\Delta$ discovered by the author over twenty years ago), proving that there is a unique distance-regular graph with intersection array {32,27,8,1;1,4,27,32}. In the process, we confirm an unpublished result of Steve Linton that there is no distance-regular antipodal double cover of $\Delta$, and so no distance-regular graph with intersection array {32,27,6,1;1,6,27,32}. We also show there is no distance-regular antipodal 4-cover of $\Delta$, and so no distance-regular graph with intersection array {32,27,9,1;1,3,27,32}, and that there is no distance-regular antipodal 6-cover of $\Delta$ that is a double cover of $\hat\Delta$., Comment: 11 pages

This paper presents biographical information about Mary Wollstonecraft (1759-1797), focusing especially on her education. The paper begins with an overview of the status of women's education, or lack of it, in 18th century England. It then describes Wollstonecraft's reaction to Jean Jacques Rousseau's views on women's education and the influence of the Ardens, a family of professional teachers, on Wollstonecraft's future work in education. (Contains 51 references.) (BT)

Two hundred years ago, Mary Wollstonecraft, the English women's rights pioneer, published her immortal work: "A Vindication of the Rights of Woman." In it she placed much of the blame for women's inferior political, intellectual, and social status on "faulty education." In "Vindication," she offered a number of recommendations aimed at enhancing the quality of education for women. These included: boys and girls schooled together and sharing a curriculum rich in experiential learning, particularly in scientific studies. She advocated physical exercise and play as well as health education specifically aimed at women's needs. These and other education proposals marked her as an important progenitor of many modern and widely accepted educational innovations. Contains 20 references. (Author)

For the past 50 years, organizations and individuals around the world have reported success in their use of action learning programs to solve problems, develop leaders, build teams and transform their corporate cultures. However, very little rigorous research has been conducted to determine the effectiveness of action learning. The authors reviewed 21 refereed articles, theses and dissertations that quantitatively and/or qualitatively measured the impact of action learning and to determine the success factors in action learning programs. The evidence elicited from these studies support the following: (1) action learning develops broad executive and managerial leadership skills, particularly collaborative leadership and coaching skills; (2) action learning improves the ability of managers to develop integrative, win/win solutions to conflict situations; (3) governing variables that were consistently identified as critical to the success of action learning include questioning, taking action, learning from group members, listening, group diversity, feelings of confidence and well-being, safe environment, and the presence of a coach; and (4) significant factors for conducting successful action learning programs involved: (1) "team-level processes" of skilled coaching, diversity, self-directed team processes, effective team presentations and review of team processes; as well as (2) "organization-level" processes of ensuring implementation of solutions, alignment and importance of the problem, support of top decision makers and the leveraging of organizational resources. (Contains 2 tables and 2 notes.)

Dominant-ethnic group conflict can be treated as either an independent or dependent variable. In this paper, dominant-ethnic conflict is discussed as the dependent variable. The paper's objectives are to: (1) present a preliminary sociological realistic theory of dominant-ethnic conflict; (2) compare and contrast the theory in terms of 2 types of models (a "static model" and processual system); (3) illustrate by the processual system the theoretical advantages of considering "feedback loops"; and (4) discuss the methodological distinctions in terms of a classification of different types of relations and linkages. The type of conflict discussed is one which is infrequent, intense, and violent. The theory holds that conflict between an ethnic and a dominant group is a function of 13 independent variables. Among these 13 variables are the competive threat, large power differences, loss of powerful friends (by dominants), gain of powerful enemies (by dominants), ethnocentrism, degree of segregation, and goal contradictions. In the "static model", all the independent variables simultaneously influence the dependent variable. In the processual system, each and every variable has both independent and dependent functions. (NQ)

Examined the thought processes of eight third graders who were learning mathematics in a small group, cooperative-learning model that paired two high-achieving and two low-achieving students. Although low achievers were active in the learning process, high achievers tended to dominate learning activities. (MDM)

This report provides considerations and suggested approaches for design of the Optical Telescope Assembly and the segmented primary mirror of a Next Generation Space Telescope (NGST). Based on prior studies and hardware development, we provide data and design information on low-risk materials and hardware configurations most likely to meet low weight, low temperature and long-life requirements of the nominal 8-meter aperture NGST. We also provide preliminary data for cost and performance trades, and recommendations for technology development and demonstration required to support the system design effort.

The Ballistic Missile Defense Organization sponsors an aggressive program to develop and demonstrate electric propulsion and space power technologies for future missions. This program supports a focused effort to design, fabricate, and space qualify a Russian Hall thruster system-on-a-pallet ready to take advantage of a near-term flight opportunity. The Russian Hall Effect Thruster Technology (RHETT) program will demonstrate an integrated pallet design in late FY95. The program also includes a parallel effort to develop advanced Solar Concentrator Arrays with Refractive Linear Element Technology (SCARLET). This synergistic technology will be demonstrated in a flight experiment this summer on the Comet satellite. This paper provides an overview of the RHETT and SCARLET programs with an emphasis on electric propulsion, recent progress, and near-term program plans.

This is an overview of the Ballistic Missile Defense Organization (BMDO) Photovoltaic Program. Areas discussed are: (1) BMDO advanced Solar Array program; (2) Brilliant Eyes type satellites; (3) Electric propulsion; (4) Contractor Solar arrays; (5) Iofee Concentrator and Cell development; (6) Entech linear mini-dome concentrator; and (7) Flight test update/plans.

Electric propulsion (EP) applications being considered include: orbit insertion, orbit repositioning, station keeping, and elusive maneuvering. Typically, 1 to 5 kW are available for EP. A class of thrusters, the Hall-effect thrusters, is extensively researched, developed and flown by Russia. These thrusters, using xenon propellant, perform reliably, e.g., at 1.35 kW, 600 s specific impulse, 50 percent efficiency and greater than 2000 hr life. This specific impulse and efficiency combination is superior to the present arcjets for several Ballistic Missile Defense Organization (BMDO) applications. Three versions of the Hall thrusters are part of the experimental evaluation. Since today's goals are within reach of available thrusters and power sources, emphasis is being placed on such topics as: thruster lifetime, spacecraft interactions, electromagnetic interference, and erosion product deposition. Facilities in U.S. laboratories are being specially configured to achieve these goals.

Presented in this document are a selection of articles written by professional educators which offer insights into education as a social institution. In a section on educational issues, some of the subjects addressed include: curricula, integration, decentralization, staffing, school financing, bilingual education, test analyses, career education, school comparisons, day care, qualified teachers and affirmative action. Classified and discussed as urban problems are: power relationships, school relevance, disadvantaged children, immigration patterns, drug abuse, discipline, health, and other social and educational issues. Unions, decision making, teacher student relationships, training, and teachers' roles are discussed in a final section dealing with the teacher as a professional. (Author/EB)

These three papers explore ways to use television for instructional purposes. "ITFS for Lifelong Learning--'The Development of a System'" (Leonard J. Bathurst) provides a brief historical overview of the background and some of the experiences at California State University, Fresno, as an Instructional Television Fixed Service (ITFS) system was developed. "Presenting Lifelong Learning Opportunities Via Instructional Television Fixed Service Channels: A National Resource" (Russ A. Hart) gives examples of existing and proposed ITFS systems designed to offer lifelong learning opportunities. "Instructional Television Fixed Services: The California State University" discusses the value and benefits of ITFS, especially as it is used at California State University. (YLB)

Using data collected at a Western State's press association convention, a study compared predicted motivation profiles for several newspaper management jobs to the actual profiles of men and women holding those jobs. In addition, the levels of job commitment and satisfaction were examined to learn how happy and dedicated the managers were. Approximately half (N=54) of the managers at the convention volunteered to write a five-minute essay in response to six pictures, and to complete a brief questionnaire that elicited demographic details and asked them to respond to a set of questions using a semantic differential scoring system designed to ascertain job satisfaction and commitment. Results showed that more than half of the subjects had a "good fit" between their actual individual needs and the needs likely to be fulfilled by their management jobs. Other findings showed that the older managers, those who had held their present jobs the longest and those who had worked in any management position the longest, were the most satisfied. No correlation was found for "good fit" and commitment. (HOD)

This report describes the results of an engineering study conducted for NASA-Lewis Research Center on Modifications to the Altitude Wind Tunnel (AWT) for Icing and Propulsion Research by DSW Engineering Corporation, Orlando, Florida and DSMA International Inc., Toronto, Canada. The engineering study referred to as study 'Part B' has been carried out under authorization of NASA Contract NAS 3-22933 (Ref. 1). The scope of work defined in the Statement of Work 3-169855 (Ref. 2) Revised 2/20/81 was discussed in detail with NASA on October 2, 1981 and covers the following areas: - Fan and Fan Housing. This includes assessment of circuit loss analyses, fan aerodynamics and mechanical conceptual design of variable and fixed pitch fans considering fixed and variable inlet guide vanes. - Fan Drive Systems - considering fixed and variable speed drives with continuous rating of 30,000 HP with overload capability of 45,000. The drive shaft between the motor and fan is to be considered and also the existing foundations for the main drive motor. - 20 ft.Test Section Arrangement - having slotted wall configurations suitable for testing at transonic velocities, with various model support systems required for the anticipated models and tests. A model handling concept aimed for high productivity testing and means for quick access to the model in the test section between test runs. - 45 ft. Test Section - feasible and practical approach for model installation and removal.

Simulation and analysis of panel separation from Apollo 13 service module

Dynamic model for obtaining response data for space shuttle

Lateral vibration characteristics of 1/10 scale Apollo/Saturn 5 replica model tested with simulated propellant loadings

Chemical vapor deposition of epitaxial gallium arsenide

Saturn 5 launch vehicle scale model tests for free vibration during first stage burn

Lumped parameter analysis of liquid filled shells with application to 1/10 scale Saturn 5 model

Dynamic scale model of lunar module type spacecraft - overturn stability for nonlevel surface landings

Dynamic model of Apollo/Saturn V launch vehicle

Lumped parameter analysis of liquid-filled shells with application to 1/10-scale Saturn V model

Digital computer techniques applied to study of impact dynamics of lunar landing vehicles

Touchdown stability tests for lunar landing vehicles - symmetrical & asymmetrical inelastic impacts

An experimental investigation was conducted to determine the effects of several basic variables upon the damping of the fundamental antisymmetric mode of liquids in right-circular cylindrical tanks without baffles. The variables examined include liquid depth, efflux rate, liquid amplitude, kinematic viscosity, and tank size. The data are presented in dimensionless form and compared with available theory. For the range of variables examined, variations of efflux rate and liquid amplitude were found to have no significant effects on the liquid damping. The following theoretical relationship was found to be adequate for the prediction of the variation of damping with liquid depth, kinematic viscosity, and tank size: [for equation see full text] where v is the kinematic viscosity, R is the cylinder radius, g is the acceleration due to gravity, and h is the liquid depth. However, the constant K was experimentally found in this investigation to have the value 5.23, which is 50 percent higher than the theoretically predicted value.

An experimental investigation was conducted to determine the damping of the fundamental antisymmetric mode of oscillation of liquids contained in an oblate spheroidal tank. The decay of the fundamental mode was studied for a range of liquid depths in tanks with and without baffles. In the investigation of baffle effects, ring and cruciform baffles of various sizes were fixed at different locations within the tank. Data presented show the variation of the damping factor with tank fullness and with baffle type, width, location, and orientation as well as the effects of the amplitude of the liquid oscillations and of small variations in the liquid kinematic viscosity on the damping factor. The results of the investigation indicate that the addition of ring baffles to the tank results in an increase in the available effective damping when the baffle plane is in a region near the equilibrium liquid surface, and that cruciform baffles are effective in the damping of the fundamental mode in the near-empty tank. No apparent changes in damping for the tanks having ring baffles were observed as the kinematic viscosity of the liquid was varied over a small range.

An experimental investigation was conducted to gain some understanding of the character of the free vibration modes of liquids In oblate spheroidal tanks applicable in missile and space vehicle systems, Measured natural frequencies were obtained for the lowest three or four, antisymmetric modes of oscillation as a function of the liquid depth for three orientations of each of several such tanks of different size and oblateness. The orientations considered were such that: (a) the equator of the spheroid was horizontal and oscillations were along a diameter of the circular liquid surface; (b) the equator of the spheroid was vertical and the oscillations were along the minor axis of the elliptical liquid surface; and (c) the equator of the spheroid was vertical and the oscillations were along the major axis of the elliptical liquid surface; The frequency data are presented as dimensionless parameters developed for each orientation to permit the application of the experimental results to the prediction of the natural frequencies of tanks of different size and oblateness. Photographs we re made of representative surface wave or mode, shapes for each orientation.

This paper presents the analysis of the flapwise natural bending frequencies and mode shapes of rotor blades with two flapping hinges located at arbitrary blade radii. The equations of motion are derived for a blade of variable mass and stiffness distribution. Solutions to the equations (natural frequencies and mode shapes) are presented for a typical blade of constant cross section having a wide range of hinge locations. The results show that the natural frequencies of the blades can be changed appreciably by varying the locations of the blade hinges, and that with two properly located flapping hinges, blade designs are possible which eliminate or greatly reduce conditions of resonance between the blade natural frequencies and the frequencies of the harmonic air loads. The results also show that ratios of natural frequency to rotor speed below a value of 6.0 are essentially constant for variations in rotor speed consistent with helicopter and VTOL applications.

Several toroidal configurations applicable to missile and space-vehicle liquid storage systems were oscillated to study the natural frequencies of the antisymmetric modes of contained liquids over a range of liquid depths and tank sizes. Natural frequencies for tank oscillations parallel to the free surface of both vertical and horizontal tank orientations. Natural frequencies were obtained. The data are presented in terms of dimensionless parameters which are obtained by relating experimentally determined natural liquid frequencies to analytical expressions developed through consideration of the physics of the problem and from existing solutions for liquids in tanks having similar boundaries at the liquid surface. The experimental results obtained for the toroids indicate that these parameters are applicable to the prediction of the natural frequencies of fluids in toroids of general geometry and size.