Induction of hemopoiesis in rat embryonic bone transplanted into adult subcutaneous connective tissue

Five pairs of immature, non-hemopoietic femur and tibia from 17-day-old gestating female rat fetuses, whose sex was determined by chromosomal analysis of liver cells, were transplanted into subcutaneous tissues of adult male rats. The original bones were about 3 mm in length and they grew to about 17 mm length at 4 wereks after transplantation. Bone deformation was not evident after transplantation and bone marrow hemopoiesis developed. Bone marrow cytohistologic observations were made on smears, and chromosome analyses were performed on bone marrow cells. Active erythro-, myelo- and megakaryopoiesis were conducted by cells of recipient adult rats. Sex chromosome analysis of cartilage cells from the epiphyses of transplanted bones demonstrated that the growing bones were composed of cells from the grafted embryo. The results thus strongly suggest that the transition of hemopoiesis from liver to bone marrow in late embryonic development is conducted by stem cells migrating through circulating blood and settling in the bone marrow and not by in situ cells differentiating in the bone marrow stroma.</p

INTEGRATIVE BIOINFORMATICS APPROACHES TO ELUCIDATING PROSTATE CANCER CELL HETEROGENEITY, PLASTICITY, AND TREATMENT RESPONSE

Prostate cancer (PCa) is the most common non-cutaneous tumor in American men, and the second leading cause of cancer-related deaths. PCa-related deaths can be attributed to heterogeneous tumors containing metastatic and therapy-resistant cancer cells. Cancer stem cells (CSC) are an important contributor to this tumor heterogeneity, which are present in primary tumors and become enriched in castration resistant PCa (CRPC). Our lab has demonstrated that the prostate cancer stem cells (PCSCs) are enriched in the phenotypically undifferentiated PCa cell population that lacks the expression of differentiation marker prostate-specific antigen (PSA). Our work has also demonstrated that PCa cells manifest significant plasticity such that phenotypically differentiated PSA+ PCa cells can be reprogrammed to the castrationresistant, stem-like state by chronic castration or overexpression of the stemness factor NANOG. Therefore, my overarching hypothesis is that PSA-/lo cells possess intrinsic molecular and epigenetic features that regulate their aggressiveness and stemness and contribute to tumor progression and therapy resistance, and that these properties can be gained through epigenetic reprogramming of more differentiated PSA+ PCa cell population. Throughout my Ph.D. thesis research, I employed an integrative bioinformatics approach to test this hypothesis

Singly Cabibbo suppressed decays of Λc+\Lambda_{c}^+ with SU(3) flavor symmetry

We analyze the weak processes of anti-triplet charmed baryons decaying to octet baryons and mesons with the SU(3) flavor symmetry and topological quark diagram scheme. We study the decay branching ratios without neglecting the contributions from ${\cal O}(\overline{15})$ for the first time in the SU(3) flavor symmetry approach. The fitting results for the Cabibbo allowed and suppressed decays of $\Lambda_{c}^+$ are all consistent with the experimental data. We predict all singly Cabibbo suppressed decays. In particular, we find that ${\cal B}(\Lambda_c^+\to p \pi^0)=(1.3\pm0.7)\times 10^{-4}$, which is slightly below the current experimental upper limit of $2.7\times 10^{-4}$ and can be tested by the ongoing experiment at BESIII as well as the future one at Belle-II.Comment: 11 pages, 2 figure, revised version accepted by PL

An analysis of the security of the Republic of China on Taiwan

Until the publication of 1992 Nien Kuo-fang Pao-kao Shu (1992 National Defence Report, Republic of China) by the Ministry of National Defence, and Kuo-fang Waichiao Pai-pi Shu (White Paper on National Defence and Diplomacy) by the Institute for National Policy Research in 1992, there was no single text or collection of readings, written from a ROC perspective or addressing issues of ROC's concern, which was available for people interested in national security. This dissertation is intended to fill that gap by broadening the theoretical and empirical evaluation of Taiwan's national security to encompass military, political and economic factors. The primary objective of this study is to develop an in-depth understanding of the ROC's approach to national security through an examination both of the dynamics of the numerous security threats confronting Taiwan and of the measures instituted to preserve and enhance national security. To accomplish this the study is divided into six chapters. Chapter 1 will provide a conceptual framework for the analysis of national security. Discussions focus on: the goal of national security; the sources and nature of threats to national security; and the measures to preserve and enhance national security. Chapter 2 considers the military dimensions of Taiwan's security. The following questions will be asked: Under what conditions might the PRC attack Taiwan? Is the PRC capable of gaining control of Taiwan by force? What are the most likely military options to be employed by the PRC should it decide to attack Taiwan? How capable is the ROC of defending itself? And what defence options are available for Taiwan? Chapter 3 examines the impact of the Taiwan independence movement (TIM) on Taiwan's political stability and national security. It centres on the following questions: What are the motives for the pursuit of Taiwan independence? What are both the ROC's and the PRC's attitudes towards the TIM? Will "self-determination" be applicable to Taiwan? And what will be the likely impact of TIM on Taiwan's security? Chapter 4 considers the economic dimension of security. GATT is used as a case study, and the implications of membership for the government and the economy of Taiwan are examined. As with any initiative, many questions have been raised. Because of Taiwan's excessive dependence on exports, its economic success depends in no small way on its ability to keep open its avenues of trade with the outside world. Cutting off those avenues could threaten both Taiwan's economic success and national security. Since survival is essential to Taiwan, in addition to the pursuit of economic growth and development, an independent war capability and sufficient forces are required for safeguarding Taiwan's security. In order to reach this goal, military modernisation is the only option. Thus, Chapter 5 will try to answer the following questions: What are the motives driving Taiwan's accelerated military modernisation? Will Taiwan be able to break through Peking's blockade and procure the weaponry needed for self-defence? Will the economy of Taiwan be able to continuously sustain such huge defence expenditures? Will the armed forces be able to recruit and retain an adequate number of skilled military personnel for the advanced and sophisticated weapons procured? And what will be the potential impacts of cross-Strait arms race on Taiwan Strait stability? In the final Chapter 6 some concluding remarks on the preceding Chapters are drawn. Taiwan should: continue its policy of cautious rapprochement with the PRC; make every effort to prevent any further deterioration in the military balance in the Taiwan Strait; use its economic success as a diplomatic tool to strengthen its relations with countries around the world

The internal intensity ratio of Hα and of Dα

A Geissler-Wood discharge tube was designed for use as the light source of Hα or Dα line. The tube was cooled in liquid air under low pressure to reveal the fine structure of the spectral lines. Four different separations, 7.6, 7.8, 8.0, and 8.2 mm, were used in the Fabry-Perot interferometer. Ten spectroscopic plates were measured for Hα and ten others for Dα. The internal intensity ratio of Hα and of Dα was found to be 0.808±0.004 and 0.803±0.003, respectively, as compared to the theoretical value of 0.806. This study indicates that the experimental value of the intensity ratio between the two main component groups agrees with the theoretical value when pure hydrogen or pure deuterium gas is used in the discharge tube and the discharge is at its maximum intensity

Efficient Computation of Group Skyline Queries on MapReduce

Skyline query is one of the important issues indatabase research and has been applied in diverse applicationsincluding multi-criteria decision support systems and so on. Theresponse of a skyline query eliminates unnecessary tuples andreturns only the user-interested result. Traditional skyline querypicks out the outstanding tuples, based on one-to-one recordcomparisons. Some modern applications request, beyond thesingular ones, for superior combinations of records. For example,fantasy basketball is composed of 5 players, fantasy baseball of 9players, and a hackathon of several programmers. Group skylineaims at considering all the groups comprising several records,and finding out the non-dominated ones. Because of the highcomplexity, few studies have been conducted and none has beenpresented in either distributed or parallel computing. This paperis the first study that solves the group skyline in the distributedMapReduce framework. We propose the MRGS algorithm togenerate all the combinations, compute the winners at each localnode, and find out the answer globally. We further propose theMRIGS algorithm to release the bottleneck of MRGS onunbalanced computing load of nodes. Finally, we propose theMRIGS-P algorithm to prune the impossible combinations andproduce indexed and balanced MapReduce computation.Extensive experiments with NBA datasets show that MRIGS-P is6 times faster than the MRGS algorithm