Rebuilding of the Temple and Renewal of Hope: Leadership Lessons from Zerubbabel, Ezra, and Nehemiah

The past three decades have been witness to a nascent but compelling body of literature on lessons in leadership for business derived from biblical narratives. The aim of this paper is to advance that effort. Specifically, this study considers the leadership of Zerubbabel, the governor of Judah, who built the Second Temple on the ruins of the First. When he arrived in Judah from Babylonia, the walls of Jerusalem were breached and the entire country was filled with people hostile to constructing the Temple. One of the mysteries of the Bible is the disappearance of Zerubbabel from the biblical record. This paper discusses mistakes made by Zerubbabel as a leader, how Ezra and Nehemiah rectified these errors, and demonstrates what leaders of today can learn from the issues involved in the construction of the Second Temple

Necrotic tumor growth: an analytic approach

The present paper deals with a free boundary problem modeling the growth process of necrotic multi-layer tumors. We prove the existence of flat stationary solutions and determine the linearization of our model at such an equilibrium. Finally, we compute the solutions of the stationary linearized problem and comment on bifurcation.Comment: 14 pages, 3 figure

Does Maternal Methadone Dose Correlate with Severity of Intrauterine Growth Restriction in Infants with Neonatal Abstinence Syndrome?

Introduction : Previous studies demonstrate a relationship between maternal opioid use during pregnancy and smaller head circumference of infants with neonatal abstinence syndrome (NAS). The goal of this study is to correlate maternal methadone dose and severity of growth restriction in infants with NAS admitted to the neonatal intensive care unit (NICU). Methods: This is a retrospective analysis of infants (≥35 weeks gestation) exposed to in utero methadone, born between August 2006 and May 2018, and admitted to a Philadelphia NICU for medical therapy for NAS. Growth parameters (birth weight, birth length, and birth head circumference) were compared between infants exposed various doses of methadone. The groups were compared using ANOVA, Post-Hoc Tukey, Chi-square and extended Fisher exact tests. Results: A total of 686 infants met the study criteria; 109 in the High dose group, 359 in the Intermediate dose group, and 218 in the Low dose group. There was no significant difference in the use of other drugs or smoking during the pregnancy. Infants exposed to higher doses of methadone displayed significantly smaller head circumferences and lengths at birth. The mean birth weight was similar between the three groups. Discussion: There may be a danger in prescribing high doses of methadone to pregnant mothers, as they may hinder the growth of the infant. We need to conduct more studies investigating how low head circumference and length affect long term developmental outcomes. These findings may help guide physicians toward the optimum dose of methadone for mothers

Covariant Uniform Acceleration

We show that standard Relativistic Dynamics Equation F=dp/d\tau is only partially covariant. To achieve full Lorentz covariance, we replace the four-force F by a rank 2 antisymmetric tensor acting on the four-velocity. By taking this tensor to be constant, we obtain a covariant definition of uniformly accelerated motion. We compute explicit solutions for uniformly accelerated motion which are divided into four types: null, linear, rotational, and general. For null acceleration, the worldline is cubic in the time. Linear acceleration covariantly extends 1D hyperbolic motion, while rotational acceleration covariantly extends pure rotational motion. We use Generalized Fermi-Walker transport to construct a uniformly accelerated family of inertial frames which are instantaneously comoving to a uniformly accelerated observer. We explain the connection between our approach and that of Mashhoon. We show that our solutions of uniformly accelerated motion have constant acceleration in the comoving frame. Assuming the Weak Hypothesis of Locality, we obtain local spacetime transformations from a uniformly accelerated frame K' to an inertial frame K. The spacetime transformations between two uniformly accelerated frames with the same acceleration are Lorentz. We compute the metric at an arbitrary point of a uniformly accelerated frame. We obtain velocity and acceleration transformations from a uniformly accelerated system K' to an inertial frame K. We derive the general formula for the time dilation between accelerated clocks. We obtain a formula for the angular velocity of a uniformly accelerated object. Every rest point of K' is uniformly accelerated, and its acceleration is a function of the observer's acceleration and its position. We obtain an interpretation of the Lorentz-Abraham-Dirac equation as an acceleration transformation from K' to K.Comment: 36 page

Revising the multipole moments of numerical spacetimes, and its consequences

Identifying the relativistic multipole moments of a spacetime of an astrophysical object that has been constructed numerically is of major interest, both because the multipole moments are intimately related to the internal structure of the object, and because the construction of a suitable analytic metric that mimics a numerical metric should be based on the multipole moments of the latter one, in order to yield a reliable representation. In this note we show that there has been a widespread delusion in the way the multipole moments of a numerical metric are read from the asymptotic expansion of the metric functions. We show how one should read correctly the first few multipole moments (starting from the quadrupole mass-moment), and how these corrected moments improve the efficiency of describing the metric functions with analytic metrics that have already been used in the literature, as well as other consequences of using the correct moments.Comment: article + supplemental materia

Rebuilding of the Temple and Renewal of Hope: Leadership Lessons from Zerubbabel, Ezra, and Nehemiah

The past three decades have been witness to a nascent but compelling body of literature on lessons in leadership for business derived from biblical narratives. The aim of this paper is to advance that effort. Specifically, this study considers the leadership of Zerubbabel, the governor of Judah, who built the Second Temple on the ruins of the First. When he arrived in Judah from Babylonia, the walls of Jerusalem were breached and the entire country was filled with people hostile to constructing the Temple. One of the mysteries of the Bible is the disappearance of Zerubbabel from the biblical record. This paper discusses mistakes made by Zerubbabel as a leader, how Ezra and Nehemiah rectified these errors, and demonstrates what leaders of today can learn from the issues involved in the construction of the Second Temple

Bagging ensemble selection for regression

Bagging ensemble selection (BES) is a relatively new ensemble learning strategy. The strategy can be seen as an ensemble of the ensemble selection from libraries of models (ES) strategy. Previous experimental results on binary classification problems have shown that using random trees as base classifiers, BES-OOB (the most successful variant of BES) is competitive with (and in many cases, superior to) other ensemble learning strategies, for instance, the original ES algorithm, stacking with linear regression, random forests or boosting. Motivated by the promising results in classification, this paper examines the predictive performance of the BES-OOB strategy for regression problems. Our results show that the BES-OOB strategy outperforms Stochastic Gradient Boosting and Bagging when using regression trees as the base learners. Our results also suggest that the advantage of using a diverse model library becomes clear when the model library size is relatively large. We also present encouraging results indicating that the non negative least squares algorithm is a viable approach for pruning an ensemble of ensembles

A numerical study of the r-mode instability of rapidly rotating nascent neutron stars

The first results of numerical analysis of classical r-modes of {\it rapidly} rotating compressible stellar models are reported. The full set of linear perturbation equations of rotating stars in Newtonian gravity are numerically solved without the slow rotation approximation. A critical curve of gravitational wave emission induced instability which restricts the rotational frequencies of hot young neutron stars is obtained. Taking the standard cooling mechanisms of neutron stars into account, we also show the `evolutionary curves' along which neutron stars are supposed to evolve as cooling and spinning-down proceed. Rotational frequencies of $1.4M_{\odot}$ stars suffering from this instability decrease to around 100Hz when the standard cooling mechanism of neutron stars is employed. This result confirms the results of other authors who adopted the slow rotation approximation.Comment: 4 pages, 2 figures; MNRAS,316,L1(2000