Renewal Capability Research Articles

THE CREATIVE IMPERATIVE: Religious Ethics and the Formation of Life in Common

Challenging a long-standing assumption of the separation of ethical from poetic activity, this essay develops the basis for a theory of moral life as inherently and radically creative. A range of contemporary post-Kantian ethicists—including Ricoeur, Nussbaum, Kearney, and Gutierrez—are employed to make the argument that moral practice requires a fundamental capability for creative transformation, imagination, and social renewal. In addition, this poetic moral capability can finally be understood only from the primordial religious point of view of the mystery of Creation as such. Humanity as an image of its Creator is called to the endless impossible possibility of the re-creation of its own complex, plural, and fallen social world. Such a perspective is opposed to views of moral life as the application of law-like principles or the recovery of past moral histories. Without a better understanding of moral life's radically creative imperative, we miss a vital element of social relations' distinctive humanity.

Searching for alternative sources of postnatal human mesenchymal stem cells: candidate MSC-like cells from umbilical cord.

Mesenchymal stem cells (MSCs) have the capability for renewal and differentiation into various lineages of mesenchymal tissues. These features of MSCs attract a lot of attention from investigators in the context of cell-based therapies of several human diseases. Despite the fact that bone marrow represents the main available source of MSCs, the use of bone marrow-derived cells is not always acceptable due to the high degree of viral infection and the significant drop in cell number and proliferative/differentiation capacity with age. Thus, the search for possible alternative MSC sources remains to be validated. Umbilical cord blood is a rich source of hematopoietic stem/progenitor cells and does not contain mesenchymal progenitors. However, MSCs circulate in the blood of preterm fetuses and may be successfully isolated and expanded. Where these cells home at the end of gestation is not clear. In this investigation, we have made an attempt to isolate MSCs from the subendothelial layer of umbilical cord vein using two standard methodological approaches: the routine isolation of human umbilical vein endothelial cell protocol and culture of isolated cells under conditions appropriate for bone-marrow-derived MSCs. Our results suggest that cord vasculature contains a high number of MSC-like elements forming colonies of fibroblastoid cells that may be successfully expanded in culture. These MSC-like cells contain no endothelium- or leukocyte-specific antigens but express alpha-smooth muscle actin and several mesenchymal cell markers. Therefore, umbilical cord/placenta stroma could be regarded as an alternative source of MSCs for experimental and clinical needs.

Generation of a Ribozyme-Adenoviral Vector Against K-ras Mutant Human Lung Cancer Cells

ras mutations represent one of the most common oncogenetic lesions in human non-small cell lung cancer (NSCLC) and adversely affect the survival of patients afflicted with this disease. ras-directed gene therapy in the past employed primarily antisense oligonucleotides (AS-ODN) or expression vectors (such as a viral vector construct) that deliver the antisense sequence to inactivate the mutant oncogene message. These approaches produced minimal toxicity, and yet were limited in efficacy. Ribozymes present a viable alternative in antisense therapy by virtue of their renewable catalytic capability for site-specific RNA cleavage. We recently produced an adenoviral vector with a hammerhead ribozyme transgene (KRbz) that is specific for the K-ras codon 12 mutant sequence GUU, given the considerations that (a) in the United States, approx 30% of human NSCLCs express K-ras oncogene mutations, nearly all of which reside in codon 12; (b) anti-K-ras, anti-H, as well as anti-N-ras hammerhead ribozymes are potent growth inhibitors in various human cancers tested; and (c) in vitro and animal model studies suggest that ribozymes directed at oncogene (K- and H-ras C-fos, BCR-ABL) or human immunodeficiency viral gene messages are more effective than their antisense counterpart. This article describes the techniques involved in the production of the KRbz-adenoviral vector that is specific for the K-ras mutation GTT, and summarizes its in vivo antitumor effect against NSCLC xenografts expressing the relevant K-ras mutation in athymic mice.

Quest for Justice as Reconciliation of the Poor and the Righteous in Psalms 37,49 and 73

The typical antithesis of the wicked and the righteous emerges in different literary works of post-exilic Israel. It is frequently combined with the motif of the shalom of the (rich and) wicked. Their fortune provokes enry and very serious challenges for the faith of those who understand themselves as the poor and the righteous. The heavy social crisis in the Persian period of the 5th and 4th century BC as well as the crisis of wisdom in this time appears as a global background of this topic. My paper examines the pursuit of justice, ie of God's justice and of the fulfilment of the frustrated religiously legitimated expectations of fortune, in the Psalms 37, 49 and 73. The intention is to realize the conflict situation presupposed by the texts and to profile the specific strategies and purposes of overcoming the conflict. The quest for justice doesn't intend a reconciliation of the poor and the rich or the wicked and the righteous. However, it leads to a "reconciliation" of the tempted pious, to a new trust in YHWH, to a new hope, and to a renewed capability of communal life.

98/03955 Renewable energy capability to save carbon emissions

98/03955 Renewable energy capability to save carbon emissions

Development of a carbon composite electrode made from polyethylene and graphite powder modified with copper(I) oxide

Solid carbon composite electrodes (CCEs) prepared by copper(I) oxide (Cu 2O) dispersed in polyethylene and graphite powder have been investigated for use as working electrode in amperometric flow-through detection in alkaline solutions. The effects of matrix composition, electrocatalyst loading, short- and long-term electrode stability, noise current, and sensitivity were assessed using d-mannitol as a model compound. Excellent sensitivity accompanied by a low residual current was observed with a 50% (w/w) Cu 2O loading level in the carbon paste matrix. An estimate value of the double layer capacitance, evaluated by cyclic voltametry in 0.48 M NaOH, was about 1360 μF/mm 2. Upon optimizing the sensing electrode in terms of composite electrode formulation, hydroxide ion concentration, and operating potential, the detection limit for d-mannitol in flow injection mode, using a wall-jet flow cell, was 5 μM for 50 μl injections. The bulk Cu 2O-CCEs exhibit good mechanical stability under forced flow hydrodynamic conditions, and overall offers the advantage of a very low background current. An additional inherent feature of these catalyst-modified electrodes is their renewal capability; the surface can rapidly be renewed by a simple polishing procedure making the amperometric sensor very attractive for routine quantitative measurements.

Development of human Th1 and Th2 cytokine responses: The cytokine production profile of T cells is dictated by the primary in vitro stimulus

Regulation of interleukin (IL)-4 production, but not IL-2 production, was found to be quite different in either freshly isolated T cells or T cell clones. Both fresh T cells and T helper 2-like clones produced IL-4 when stimulated with anti-CD2 in combination with anti-CD28. However, whereas T cell clones showed enhanced IL-4 production when phorbol 12-myristate 13-acetate (PMA) was used in addition to anti-CD2 and anti-CD28, IL-4 production by fresh T cells was inhibited by the presence of PMA. Prestimulation of fresh T cells led to the following observations: (a) activation in the absence of PMA led to a reversal of the PMA effect and (b) within 2 days these cells resembled T cell clones in that IL-4 production was no longer inhibited by PMA. When prestimulation was carried out in the presence of PMA, the inhibition of IL-4 production seemed irreversible. Removal of PMA after 3 days did not lead to renewed capability of IL-4 production, whereas IL-2 production was unimpaired. Our data show that the capacity of cultured T cells to produce IL-4 is determined and fixed during the first 2-3 days of stimulation.

A short-term in vitro drug-screening assay for cancer chemotherapy.

In this short-term in vitro assay for detection of tumor cell sensitivity to drugs, we have replaced the traditional soft-agar colony-forming assay with the measurement of DNA synthesis, to determine the cell renewal capability of the tumor cell population. The tumor cells are treated with drugs and cultured for five days. During the last 12--18 h of culture the cells are pulsed with [3H]thymidine, then harvested for scintillation counting. The effects of drugs are expressed as the percentage of DNA synthesis as compared with that of the control. When the % DNA synthesis is less than 40%, the drug is considered to be effective. So far we have studied tumor cells from multiple myeloma, non-Hodgkin's lymphoma, and carcinoma of lung, breast, ovary, stomach, and bladder. The overall negative predictive value is 1.0. The results are available within five days, compared with 21--28 days for completion of soft-agar assays; fewer cells are required; and the process is semiautomated.

Mixing corrosion in CaCO 3/1bCO 2/1bH 2O systems and its role in the karstification of limestone areas

Mixtures of two saturated H 2O/1bCO 2/1bCaCO 3 solutions of different chemical composition gain renewed capability of dissolving calcite. This is an important mechanism in the solution processes of limestone during karstification. Using recent data on the kinetics of calcite dissolution, dissolution rates in mixture corrosion are calculated. In the region of the chemical composition of natural karst waters the solution rate is approximated by: R=−α([ Ca 2+] − [ Ca 2+] s where [Ca 2+], [Ca 2+] s are the concentrations of the Ca 2+ ion in the solution and at saturation, respectively. α ranges from 10 −4 to 3·10 −4 cm s −1. This result is applied to the solution of limestone in karst water mixtures flowing in cylindrical conduits. The saturation length, i.e. the length x s which the solution has to travel to drop to 37% of its renewed dissolving capability, is calculated in the region of turbulent flow. This region starts at conduit radii R of several millimeters. At the onset of turbulent flow the saturation length is 260 m, increasing with R 1.665. The increase of conduit radii is calculated from the dissolution rates of calcite solution to be on the order of 10 −3 cm yr. −1. The results are discussed for a comprehensive model of karstification and cave development, which for the first time gives a realistic theoretical time region for cave development, in agreement to experience.

Optimal Control of Unreliable Dynamic Systems with Discrete Time Inspections

The optimal control of unreliable dynamic systems where the mode (working or failed) is continuously inspected or monitored has received attention in the past. We consider the problem where instead of continuous inspection we have either no inspection or inspection at discrete time instants. The optimal feedback control is derived for the case where the system has no renewable capabilities. The case where a fixed number of renewals are allowed is briefly discussed.

Uniform performance-adaptive renewal policies for linear systems

The model for a linear system with renewal capability presented by Ratner and Luenberger [1] is investigated. An algorithm is given for determining a region over which immediate renewal is the optimal policy. The optimal feedback gains are given for system operation with immediate renewal. A scalar example illustrates the utilization of the algorithm.

Performance-adaptive renewal policies for linear systems

The design of systems with a component subject to failure may include a discrete renewal capability to counter the degradation in performance caused by improper operation of the failed component. A solution is presented to the problem of determining the optimal use of available renewal capability for first-order time-varying linear systems with a quadratic performance index, using an exponential model of component failure. The solution is extended quasi optimally to linear systems of arbitrary order. The renewal policy determined is performance-adaptive in the sense that it depends on the failure and renewal histories of the system and on their relation to future operating requirements. The renewal policy is determined with respect to other control variables to insure overall optimal performance. A discrete stage variable is introduced to specify the system operating condition. The optimal control and renewal policy within each stage is specified by a pair of Riccati equations whose solutions are precomputed. The method avoids quantization of continuous-valued state variables, thereby lessening the effects of the curse of dimensionality.