How and why network governance evolves: evidence from a public safety network

Public sector organizations increasingly form interorganizational networks that rely on technology to achieve what they cannot achieve independently. The governance of these public sector networks is complex due to the nature of interorganizational relationships and technology. This paper aims to increase our understanding of network governance by exploring the evolution of governance over the 40+ year lifespan of a public sector network. The historical case study is based on the technology affordance and organizational actualization concepts applied to three critical incidents in the history of a public safety network. The incidents provide evidence that technology and governance do interact, that timing matters and that future research is needed to understand more fully how and why network governance evolves and the implications of governance evolution on network performance.     

Comparison of perceived comfort differences between standard and experimental load carriage systems

The current popularity of backpack-type load carriage systems (LCS) by students has precipitated a prevalence of postural abnormalities and pain. This study compared subjective perceptual comfort in standard and vertically loaded LCSs. Sixteen females ages 18-23 years rated their personal LCSs for perceived shoulder, neck, and lower back comfort and for overall comfort, each day for two weeks using 100 mm visual analogue scales (VAS). Each scale contained polar extremities of 'very comfortable' to 'very uncomfortable' and a vertical mark placed on the 100 mm line by the participants indicated their perception of comfort. Following two weeks, participants were given LCSs that distributed the weight vertically and were asked to rate the system in the same way for an additional two-week period. Statistical analysis revealed significant differences in shoulder (p=0.015), neck (p=0.005), and lower back (p=0.036) comfort and overall comfort (p=0.001) between the participants' personal LCSs and the experimental LCS. In conclusion, vertical load placement may redistribute the load in a manner that reduces symptoms of selected anatomical discomfort.     

NMR studies on HxTaS2 and DxTaS2

H_0.33TaS₂ and D_0.33TaS₂ have been prepared electrochemically and their magnetic resonance properties investigated. The ²D quadrupole coupling constant and ¹H spin-lattice relaxation rates have been measured and are similar to the same quantities measured in transition metal hydrides. Spin-spin relaxation rate data show that the hydrogen is immobile on an NMR time scale. These results are consistent with earlier structural conclusions from neutron diffraction studies, which locate the H within the TaS₂ layers.     

On zero-order hold equivalents of distributed parameter systems

Various connections are established between linear time-invariant distributed parameter continuous-time systems and their zero-order hold discrete-time equivalents. These connections are established in both the time and frequency domains. The time-domain connections relate various growth constants and norm bounds of the continuous-time systems considered to those of their zero-order hold discrete-time equivalents. The frequency-domain connection provides an upper bound on the difference between the frequency response of a continuous-time system and that of its zero-order hold discrete-time equivalent     

The stability of preferences for life-sustaining care among persons with AIDS in the Boston Health Study

In 1982, the World Health Organization (WHO) identified inadequate relief from cancer pain as an international health problem. WHO recommended that governments develop and implement national policies and programs for cancer pain relief. This report evaluates national health policy and the systems of health care delivery in relation to cancer pain management in the new South Africa. This field study included multiple methods of data collection: analysis of documents, field trips with participant observation in sites of care delivery, focused interviews, and in-depth interviews of key informants. The purposive sample of key informants (n = 33) represented multiple stakeholders in a variety of settings. Strengths of the developing health policy include specific recommendations related to palliative care; the shift to universal primary care; policies to support drug availability; the inclusion of morphine and codeine as essential drug at the primary health care level; and the development of a national standard related to cancer pain management. Health services are characterized by two parallel systems of care (private and public) with numerous vestiges of the inequities of apartheid. The management of pain varies by provider and setting; major problems with access exist in the rural areas. Health services in South Africa have been plagued by inequity and inadequate resources. New health policies have set a path to ensure universal access to health care including palliative care for cancer. Their successful implementation is the next necessary step toward improving health services and alleviating the suffering of increasing numbers of individuals with cancer.     

Gravity is an important but secondary determinant of regional pulmonary blood flow in upright primates

Original studies leading to the gravitational model of pulmonary blood flow and contemporary studies showing gravity-independent perfusion differ in the recent use of laboratory animals instead of humans. We explored the distribution of pulmonary blood flow in baboons because their anatomy, serial distribution of vascular resistances, and hemodynamic responses to hypoxia are similar to those of humans. Four baboons were anesthetized with ketamine, intubated, and mechanically ventilated. Different colors of fluorescent microspheres were given intravenously while the animals were in the supine, prone, upright (repeated), and head-down (repeated) postures. The animals were killed, and their lungs were excised, dried, and diced into approximately 2-cm3 pieces with the spatial coordinates recorded for each piece. Regional blood flow was determined for each posture from the fluorescent signals of each piece. Perfusion heterogeneity was greatest in the upright posture and least when prone. Using multiple-stepwise regression, we estimate that 7, 5, and 25% of perfusion heterogeneity is due to gravity in the supine, prone, and upright postures, respectively. Although important, gravity is not the predominant determinant of pulmonary perfusion heterogeneity in upright primates. Because of anatomic similarities, the same may be true for humans.     

Relationship between behavioral marital therapy outcome and process variables.

This study was conducted to identify therapist and client behaviors with a positive response to social learning-based behavioral marital therapy. A sample of 32 couples receiving treatment was examined. Immediately after each therapy session, the therapist, husband, and wife independently completed process ratings forms that measured therapist and client behaviors during the session. Composite scales, derived from these ratings, were entered into multiple regression equations to examine their relationship with posttherapy marital satisfaction. After controlling for pretherapy marital satisfaction and the other predictor variables, therapists', husbands', and wives' ratings of positive client behavior (i.e., collaboration, active participation, and homework compliance) were positively associated with therapy outcome. Implications for marital therapy and suggestions for future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Suppression of tumorigenicity of rat liver epithelial tumor cell lines by a putative human 11p11.2-p12 liver tumor suppressor locus

We have previously identified and mapped a locus within human chromosome 11p11.2-p12 that suppresses the tumorigenic potential of a rat liver tumor cell line (termed GN6TF) which contains well defined chromosomal aberrations involving rat chromosomes 1, 4, 7, and 10. In the present study, we investigated the potential of this human 11p11.2-p12 liver tumor suppressor locus to suppress the tumorigenic potential of two other rat liver tumor cell lines (GN3TG and GP10TA) following microcell-mediated introduction of human chromosome 11. These tumor cell lines are aneuploid and contain chromosomal abnormalities that are similar to the GN6TF tumor line. The tumorigenic potential and other phenotypic characteristics of GN3TG-11neo and GP10TA-11neo microcell hybrid (MCH) cell lines were variable, and dependent upon the status of the introduced human chromosome 11. MCH cell lines that retained the region of 11p11. 2-p12 delineated by microsatellite markers D11S1385 and D11S903 exhibited suppression of tumorigenicity in vivo (decrease in tumorigenicity and/or elongation of latency), whereas, the tumorigenic potential of one MCH line that lacked markers in this region of human 11p11.2-p12, but retained flanking markers, was not changed from that of the parental tumor cell line. The chromosomal interval between microsatellite markers D11S1385 and D11S903 encompasses the previously localized minimal liver tumor suppressor region, suggesting that a common locus is responsible for tumor suppression among the rat liver tumor cell lines examined. The results of the present study have verified the presence of a liver tumor suppressor locus within human 11p11.2-p12, and have identified a substantial number of microsatellite markers that are closely linked to this tumor suppressor region. These chromosomal markers will facilitate positional cloning of candidate genes from this region, and may prove useful for determining the involvement of this locus in the pathogenesis of human liver cancer.     

Structure-based design of inhibitors specific for bacterial thymidylate synthase

Thymidylate synthase is an attractive target for antiproliferative drug design because of its key role in the synthesis of DNA. As such, the enzyme has been widely targeted for anticancer applications. In principle, TS should also be a good target for drugs used to fight infectious disease. In practice, TS is highly conserved across species, and it has proven to be difficult to develop inhibitors that are selective for microbial TS enzymes over the human enzyme. Using the structure of TS from Lactobacillus casei in complex with the nonsubstrate analogue phenolphthalein, inhibitors were designed to take advantage of features of the bacterial enzyme that differ from those of the human enzyme. Upon synthesis and testing, these inhibitors were found to be up to 40-fold selective for the bacterial enzyme over the human enzyme. The crystal structures of two of these inhibitors in complex with TS suggested the design of further compounds. Subsequent synthesis and testing showed that these second-round compounds inhibit the bacterial enzyme at sub-micromolar concentrations, while the human enzyme was not inhibited at detectable levels (selectivities of 100-1000-fold or greater). Although these inhibitors share chemical similarities, X-ray crystal structures reveal that the analogues bind to the enzyme in substantially different orientations. Site-directed mutagenesis experiments suggest that the individual inhibitors may adopt multiple configurations in their complexes with TS.