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One of the most important processing steps in any analysis pipeline is handling missing data. Traditional approaches simply delete any sample or feature with missing elements. Recent imputation methods replace missing data based on assumed relationships between observed data and the missing elements. However, there is a largely under-explored alternative amid these extremes. Partial deletion approaches remove excessive amounts of missing data, as defined by the user. They can be used in place of traditional deletion or as a precursor to imputation. In this manuscript, we expand upon the Mr. Clean suite of algorithms, focusing on the scenario where all missing data is removed. We show that the RowCol Integer Program can be recast as a Linear Program, thereby reducing runtime. Additionally, the Element Integer Program can be reformulated to reduce the number of variables and allow for high levels of parallelization. Using real-world data sets from genetic, gene expression, and single cell RNA-seq experiments we demonstrate that our algorithms outperform existing deletion techniques over several missingness values, balancing runtime and data retention. Our combined greedy algorithm retains the maximum number of valid elements in 126 of 150 scenarios and stays within 1\% of maximum in 23 of the remaining experiments. The reformulated Element IP complements the greedy algorithm when removing all missing data, boasting a reduced runtime and increase in valid elements in larger data sets, over its generic counterpart. These two programs greatly increase the amount of valid data retained over traditional deletion techniques and further improve on existing partial deletion algorithms., Comment: 11 pages, 6 figures

On 15 May 2020 an MWW 6.5 earthquake occurred beneath the Monte Cristo Range in the Mina Deflection region of western Nevada. Rapid deployment of eight temporary seismic stations enables detailed analysis of its productive and slowly decaying aftershock sequence (p=0.8) which included ~18,000 autodetected events in 3.5 months. Double-difference, waveform-based relative relocation of 16,714 earthquakes reveals a complex network of faults, many of which cross the inferred 35-km long east-northeast-striking, left-lateral mainshock rupture. Seismicity aligns with left-lateral, right-lateral, and normal mechanism moment tensors of 128 of the largest earthquakes. The mainshock occurred near the middle of the aftershock zone at the intersection of two distinct zones of seismicity. In the western section, numerous subparallel, shallow, north-northeast-striking faults form a broad flower-structure-like fault mesh that coalesces at depth into a near-vertical, left-lateral fault. We infer the near-vertical fault to be a region of significant slip in the mainshock and an eastward extension of the left-lateral Candelaria fault. Near the mainshock hypocenter, seismicity occurs on a northeast-striking, west-dipping structure which extends north from the Eastern Columbus Salt Marsh normal fault. Together, these two intersecting structures bound the Columbus Salt Marsh tectonic basin. East of this intersection and the mainshock hypocenter, seismicity occurs in a narrow, near-vertical, east-northeast-striking fault zone through to its eastern terminus. At the eastern end, the aftershock zone broadens and extends northwest towards the southern extension of the northwest-striking, right-lateral Petrified Springs fault system. The eastern section hosts significantly fewer aftershocks than the western section, but has more moment release.

Hydrogen-rich, core-collapse supernovae are typically divided into four classes: IIP, IIL, IIn, and IIb. In general, interaction with circumstellar material is only considered for Type IIn supernovae. However, recent hydrodynamic modeling of IIP and IIL supernovae requires circumstellar material to reproduce their early light curves. In this scenario, IIL supernovae experience large amounts of mass loss before exploding. We test this hypothesis on ASASSN-15oz, a Type IIL supernova. With extensive follow-up in the X- ray, UV, optical, IR, and radio we present our search for signs of interaction, and the mass-loss history indicated by their detection. We find evidence of short-lived intense mass-loss just prior to explosion from light curve modeling, amounting in 1.5 M$_{\odot}$ of material within 1800 R$_{\odot}$ of the progenitor. We also detect the supernova in the radio, indicating mass-loss rates of $10^{-6}-10^{-7}$ M$_{\odot}$ yr$^{-1}$ prior to the extreme mass-loss period. Our failure to detect the supernova in the X-ray and the lack of narrow emission lines in the UV, optical, and NIR do not contradict this picture and place an upper limit on the mass-loss rate outside the extreme period of $<10^{-4}$ M$_{\odot}$ yr$^{-1}$. This paper highlights the importance gathering comprehensive data on more Type II supernovae to enable detailed modeling of the progenitor and supernova which can elucidate their mass-loss histories and envelope structures and thus inform stellar evolution models., Comment: Submitted to MNRAS including referee comments

We report the discovery of a $H_r = 3.4\pm0.1$ dwarf planet candidate by the Pan-STARRS Outer Solar System Survey. 2010 JO$_{179}$ is red with $(g-r)=0.88 \pm 0.21$, roughly round, and slowly rotating, with a period of $30.6$ hr. Estimates of its albedo imply a diameter of 600--900~km. Observations sampling the span between 2005--2016 provide an exceptionally well-determined orbit for 2010 JO$_{179}$, with a semi-major axis of $78.307\pm0.009$ au, distant orbits known to this precision are rare. We find that 2010 JO$_{179}$ librates securely within the 21:5 mean-motion resonance with Neptune on hundred-megayear time scales, joining the small but growing set of known distant dwarf planets on metastable resonant orbits. These imply a substantial trans-Neptunian population that shifts between stability in high-order resonances, the detached population, and the eroding population of the scattering disk.

The Professional Nurse Traineeship (PNT) program was created to provide nursing schools that place high proportions of their graduates in medically underserved communities with additional funding to support students in graduate nursing education or training. A total of 4,332 nurses who graduated in the academic years of 1996-1997 or 1997-1998 from schools receiving PNT funds were surveyed regarding their graduate training experiences, employment after graduation, and education before entering graduate school. Univariate and bivariate analyses of the 3,219 responses (response rate, 74.5%) established that, although the PNT program is meeting its performance goal of placing 40% of its graduate recipients in medically underserved communities, schools with funding preference actually had lower rates of graduates employed in medically underserved communities than did schools without the preference. Some school practices found in schools with and without funding preferences (such as requiring nurses to take courses on providing health care services in rural or medically underserved communities and requiring nurses to sign a commitment to practice in medically underserved communities) and some demographic factors (such as non-White race and Hispanic ethnicity) were associated with higher rates of employment in medically underserved communities. The survey and weighting methodology as well as the selected results by year of graduation are appended. (Contains 23 tables and 5 references.) (MN)

Noting that the quality of early childhood education (ECE) programs offered in public schools is directly affected by the understanding of and value placed on such a program by the building principal, this qualitative study examined principals' understanding and beliefs about children's play and its place in K-2 early childhood programs. Phase 1 of the study involved gathering group survey data on general beliefs about ECE. Findings from Phase 1 suggested that the administrators scored high on the developmentally appropriate practice scale (DAP) and low on the traditional practices (TRAD) scale. Phase 2 involved the selection of four participants representing four belief types: (1) low DAP, high TRAD beliefs; (2) high DAP, low TRAD; (3) high DAP, high TRAD; and (4) low DAP, low TRAD. Individual hour-long interviews were audiotaped and transcribed. The overriding theme emerging from the transcripts was that the principals overestimated their level of expertise about children's play and displayed unwarranted confidence in their ability to deal with issues regarding its role in ECE. Principals lacked relevant preparation and experience, lacked specific knowledge about play, and lacked understanding about its curricular role. (Contains 65 references.) (KB)

This study explored relationships between children's multidimensional self-concepts and teachers' beliefs about developmentally appropriate practices (DAP). Twenty-three boys and 28 girls were given the Self Description Questionnaire-I (SDQ-I) twice to measure multidimensional self-concept; their teachers were given the Primary Teacher Questionnaire to measure beliefs about traditional versus developmentally appropriate practices. Multiple regression analyses to predict the children's later self-concept score from the earlier SDQ-I scores and teacher beliefs showed that traditional practices predicted general school self-concept for boys, but that DAP was not a predictor of any dimension of self-concept. Correlational analyses showed that for boys, DAP and traditional practices both were positively related to several of the academic self-concept scales of the SDQ-I, but for girls DAP was inversely related to physical ability self-concept. Findings pose contradictions to the literature on DAP and child outcomes. (Contains 67 references.) (Author/EV)

This report describes the development of the Primary Teacher Questionnaire (PTQ), a self-report teacher beliefs scale based on the position statement on developmentally appropriate practice in the primary grades published by the National Association for the Education of Young Children (NAEYC). The development of the PTQ was conducted in three phases, item development, initial testing and scale refinement, and field testing. In the field test, a 42-item version of the PTQ was administered to 144 elementary and early childhood preservice and inservice teachers. This version of the PTQ consisted of two subscales that related to developmentally based and traditionally based practices. Results of the testing indicated that the two PTQ subscales highly differentiated respondents on the basis of their background in early childhood education, and were internally consistent. Factor analysis of the 42 items identified 2 factors. It is concluded that the PTQ is a useful instrument for examining teacher beliefs about appropriate practice in primary school settings. Seven tables of statistics, and a copy of the PTQ are appended. (Contains 37 references.) (PM)

Finite element model correlation as part of a spacecraft program has always been a challenge. For any NASA mission, the coupled system response of the spacecraft and launch vehicle can be determined analytically through a Coupled Loads Analysis (CLA), as it is not possible to test the spacecraft and launch vehicle coupled system before launch. The value of the CLA is highly dependent on the accuracy of the frequencies and mode shapes extracted from the spacecraft model. NASA standards require the spacecraft model used in the final Verification Loads Cycle to be correlated by either a modal test or by comparison of the model with Frequency Response Functions (FRFs) obtained during the environmental qualification test. Due to budgetary and time constraints, most programs opt to correlate the spacecraft dynamic model during the environmental qualification test, conducted on a large shaker table. For any model correlation effort, the key has always been finding a proper definition of the boundary conditions. This paper is a correlation case study to investigate the difference in responses of a simple structure using a free-free boundary, a fixed boundary on the shaker table, and a base-drive vibration test, all using identical instrumentation. The NAVCON Jim Beam test structure, featured in the IMAC round robin modal test of 2009, was selected as a simple, well recognized and well characterized structure to conduct this investigation. First, a free-free impact modal test of the Jim Beam was done as an experimental control. Second, the Jim Beam was mounted to a large 20,000 lbf shaker, and an impact modal test in this fixed configuration was conducted. Lastly, a vibration test of the Jim Beam was conducted on the shaker table. The free-free impact test, the fixed impact test, and the base-drive test were used to assess the effect of the shaker modes, evaluate the validity of fixed-base modeling assumptions, and compare final model correlation results between these boundary conditions.

The urban, ethnically Hawaiian child typically experiences great difficulty in learning to read English. In order to determine whether phonological confusion is a source of dialectical interference, the Kamehameha Early Education Program (KEEP) Phone Discrimination Test (KPDT) was developed for the one hundred twelve students in the KEEP school (K-3). This research report describes the development of the procedure for item inclusion and for administration of the test. The research sought to answer the following questions: (1) whether bidialectal confusion difficulties should be assumed, (2) whether all confusions of this sort are idiosyncratic in nature, and (3) whether there is a need for a program to eliminate confusions due to differing phoneme inventories of an idiolectal or dialectal nature. Eight Hawaiian-Creole-speaking children selected by KEEP personnel were the subjects in the development of the test. The final version concentrates on five phoneme pairs which appear to be sources of allophonemic confusion for the children tested. It appears to test (at the allophonemic level) points of overall phonemic confusion which could be predicted to be sources of difficulty in learning phoneme-grapheme correspondence. This report includes a test sample and directions for its administration and use. (AMH)

The purpose of this study was to examine the interrelationships among five measures of aided reading comprehension (reading to each subject while he silently reads or follows along), intelligence, and three measures of cognitive style variables in first grade children. Thirty-four first graders, 13 boys and 21 girls, served as subjects. It was concluded that cognitive style tests can provide useful information to a reading teacher. The role which cognitive style variables play in terms of current conceptual and theoretical models of reading comprehension processed should continue to be examined. (Author/RB)

North Chicago, Illinois, District 187, received a districtwide overhaul of lighting, heating, ventilation, and security systems through a 10-year performance contract with the Honeywell Corporation. The Briarcliff Manor Union-Free School District, New York, has a contract with Johnson Controls that guarantees a portion of the energy savings generated through a project. (MLF)

Describes how IBM's "LinkWay" hypertext program was used in the Tuba City Boarding School (Navajo Reservation) to develop reading improvement programs and to allow students to develop their own productions. Notes that the program addresses the cooperative, noncompetitive nature of the Navajo learning style, and the problems of unfamiliar content and lack of immediate purpose. (SR)

In this design, single-wall carbon nanotubes (SWNTs) have been coated in polymer molecules to create a new type of material that has low electrical conductivity, but still contains individual nanotubes, and small ropes of individual nanotubes, which are themselves good electrical conductors and serve as small conducting rods immersed in an electrically insulating matrix. The polymer is attached through weak chemical forces that are primarily non-covalent in nature, caused primarily through polarization rather than the sharing of valence electrons. Therefore, the electronic structure of the SWNT involved is substantially the same as that of free, individual (and small ropes of) SWNT. Their high conductivity makes the individual nanotubes extremely electrically polarizable, and materials containing these individual, highly polarizable molecules exhibit novel electrical properties including a high dielectric constant.

This paper discussed the thermal design and performance of the 6-meter hydroformed reflector antenna as well as projecting the performance of the Square Kilometer Array (SKA) 12-meter antenna.

As the International Space Station (ISS) grows, so do the supplies and equipment needed to support its daily operations. Each day many items must be unstowed and moved to various worksites so that they are readily available to the crew. Due to the lack of gravity, these items ,may become loose and float away if not restrained. The Payload Equipment Restraint System (PERS) was developed to meet the new and unique challenge of restraining loose equipment aboard the ISS.

As the International Space Station (ISS) grows, so do the supplies and equipment needed to support its daily operations. Each day many items must be unstowed and relocated to various worksites so they are readily available to the crew. Due to the lack of gravity, these items may become loose and float away if not restrained. The Payload Equipment Restraint System was developed to meet the new and unique challenge of restrain no loose equipment aboard the ISS.

The Cassini spacecraft mission to Saturn will be launched in October 1997, on a Titan IV/Centaur launch vehicle. Cassini is the largest interplanetary spacecraft ever developed. Before launch approval can be obtained, a test verified finite element model of the Cassini spacecraft must be completed and approved by NASA. The correctness of this model is critical to the final verification coupled loads analysis and margin of safety assessments.

Prior to atmospheric entry, Mars Pathfinder flight system will separate its entry vehicle from its cruise stage, and establish the entry conditions for a passive and unconventional entry, descent, and landing approach. This paper summarizes a separation dynamics analysis conducted to demonstrate that the cruise separation system design is viable and ensure that adequate design margins exist with the effects from parameter uncertainty included.

UNKNOWN

There has been an increased interest recently in developing alternatives to fixed-base modal testing for verification of large Space Shuttle payloads. A promising approach is free-free modal testing, augmented with residual flexibility measurements obtained from interface verification testing. This paper presents summary results from the recent free-free test performed on the Shuttle Imaging Radar-C payload.

Training astronaut and ground controllers for payload operations onboard Space Station Freedom presents challenges not found in precursor programs such as Skylab and Spacelab. The evolution from current Spacelab payload training concepts is discussed, and the proposed SSF payload training approach is presented along with development strategies and recommendations.

This paper summarizes a dynamic analysis conducted in support of the investigation of the anomalous deployment of the Galileo High Gain Antenna on April 11, 1991. The work was focused on modeling the spacecraft spin dynamics to predict and compare the spin detector telemetry during the antenna deployment for possible cause scenarios. The effects of analog and digital low-pass filtering, digitization, and telemetry on the reported spin rate were studied as well. The high frequency phenomena in the spin detector response are masked by the filtering and sampling of the telemetry data. However, the observed spin detector telemetery is consistent with a single rib popping free, and is most likely associated with a rib near the spin detector, or 180 deg opposite.

An incremental modal survey performed in 1988 on the core structure of the Galileo spacecraft with its adapters with the purpose of assessing the dynamics of the new portions of the structure is considered. Emphasis is placed on the enhancements of the sine dwell method employed in the test. For each mode, response data is acquired at 32 frequencies in a narrow band enclosing the resonance, utilizing the SWIFT technique. It is pointed out that due to the simplicity of the data processing involved, the diagnostic and modal-parameter data is available within several minutes after data acquisition; however, compared with straight curve-fitting approaches, the method requires more time for data acquisition.