237 research outputs found
Epistemic and Ontic Quantum Realities
Quantum theory has provoked intense discussions about its interpretation since its pioneer days. One of the few scientists who have been continuously engaged in this development from both physical and philosophical perspectives is Carl Friedrich von Weizsaecker. The questions he posed were and are inspiring for many, including the authors of this contribution. Weizsaecker developed Bohr's view of quantum theory as a theory of knowledge. We show that such an epistemic perspective can be consistently complemented by Einstein's ontically oriented position
Facilitation of Male Sexual Behavior in Syrian Hamsters by the Combined Action of Dihydrotestosterone and Testosterone
Testosterone (T) controls male Syrian hamster sexual behavior, however, neither of T's primary metabolites, dihydrotestosterone (DHT) and estradiol (E(2)), even in highly supraphysiological doses, fully restores sexual behavior in castrated hamsters. DHT and T apparently interact with androgen receptors differentially to control male sexual behavior (MSB), but whether these two hormones act synergistically or antagonistically to control MSB has received scant experimental attention and is addressed in the present study.Sexually experienced male Syrian hamsters were gonadectomized and monitored 5 weeks later to confirm elimination of the ejaculatory reflex (week 0), at which time they received subcutaneous DHT-filled or empty capsules that remained in situ for the duration of the experiment. Daily injections of a physiological dose of 25 µg T or vehicle commenced two weeks after capsule implantation. MSB was tested 2, 4 and 5 weeks after T treatment began. DHT capsules were no more effective than control treatment for long-term restoration of ejaculation. Combined DHT + T treatment, however, restored the ejaculatory reflex more effectively than T alone, as evidenced by more rapid recovery of ejaculatory behavior, shorter ejaculation latencies, and a greater number of ejaculations in 30 minute tests.DHT and T administered together restored sexual behavior to pre-castration levels more rapidly than did T alone, whereas DHT and vehicle were largely ineffective. The additive actions of DHT and T on MSB are discussed in relation to different effects of these androgens on androgen receptors in the male hamster brain mating circuit
Identifying and Characterizing a Novel Protein Kinase STK35L1 and Deciphering Its Orthologs and Close-Homologs in Vertebrates
The human kinome containing 478 eukaryotic protein kinases has over 100 uncharacterized kinases with unknown substrates and biological functions. The Ser/Thr kinase 35 (STK35, Clik1) is a member of the NKF 4 (New Kinase Family 4) in the kinome with unknown substrates and biological functions. Various high throughput studies indicate that STK35 could be involved in various human diseases such as colorectal cancer and malaria. In this study, we found that the previously published coding sequence of the STK35 gene is incomplete. The newly identified sequence of the STK35 gene codes for a protein of 534 amino acids with a N-terminal elongation of 133 amino acids. It has been designated as STK35L (STK35 long). Since it is the first of further homologous kinases we termed it as STK35L1. The STK35L1 protein (58 kDa on SDS-PAGE), but not STK35 (44 kDa), was found to be expressed in all human cells studied (endothelial cells, HeLa, and HEK cells) and was down-regulated after silencing with specific siRNA. EGFP-STK35L1 was localized in the nucleus and the nucleolus. By combining syntenic and gene structure pattern data and homology searches, two further STK35L1 homologs, STK35L2 (previously known as PDIK1L) and STK35L3, were found. All these protein kinase homologs were conserved throughout the vertebrates. The STK35L3 gene was specifically lost during placental mammalian evolution. Using comparative genomics, we have identified orthologous sets of these three protein kinases genes and their possible ancestor gene in two sea squirt genomes. We found the full-length coding sequence of the STK35 gene and termed it as STK35L1. We identified a new third STK35-like gene, STK35L3, in vertebrates and a possible ancestor gene in sea squirt genome. This study will provide a comprehensive platform to explore the role of STK35L kinases in cell functions and human diseases
Formation of Complex and Unstable Chromosomal Translocations in Yeast
Genome instability, associated with chromosome breakage syndromes and most human
cancers, is still poorly understood. In the yeast Saccharomyces
cerevisiae, numerous genes with roles in the preservation of genome
integrity have been identified. DNA-damage-checkpoint-deficient yeast cells that
lack Sgs1, a RecQ-like DNA helicase related to the human
Bloom's-syndrome-associated helicase BLM, show an increased rate of
genome instability, and we have previously shown that they accumulate recurring
chromosomal translocations between three similar genes, CAN1,
LYP1 and ALP1. Here, the chromosomal
location, copy number and sequence similarity of the translocation targets
ALP1 and LYP1 were altered to gain insight
into the formation of complex translocations. Among 844 clones with chromosomal
rearrangements, 93 with various types of simple and complex translocations
involving CAN1, LYP1 and ALP1
were identified. Breakpoint sequencing and mapping showed that the formation of
complex translocation types is strictly dependent on the location of the
initiating DNA break and revealed that complex translocations arise via a
combination of interchromosomal translocation and template-switching, as well as
from unstable dicentric intermediates. Template-switching occurred between
sequences on the same chromosome, but was inhibited if the genes were
transferred to different chromosomes. Unstable dicentric translocations
continuously gave rise to clones with multiple translocations in various
combinations, reminiscent of intratumor heterogeneity in human cancers. Base
substitutions and evidence of DNA slippage near rearrangement breakpoints
revealed that translocation formation can be accompanied by point mutations, and
their presence in different translocation types within the same clone provides
evidence that some of the different translocation types are derived from each
other rather than being formed de novo. These findings provide
insight into eukaryotic genome instability, especially the formation of
translocations and the sources of intraclonal heterogeneity, both of which are
often associated with human cancers
Experimental and theoretical studies of nanofluid thermal conductivity enhancement: a review
Nanofluids, i.e., well-dispersed (metallic) nanoparticles at low- volume fractions in liquids, may enhance the mixture's thermal conductivity, knf, over the base-fluid values. Thus, they are potentially useful for advanced cooling of micro-systems. Focusing mainly on dilute suspensions of well-dispersed spherical nanoparticles in water or ethylene glycol, recent experimental observations, associated measurement techniques, and new theories as well as useful correlations have been reviewed
Enhancing innovation between scientific and indigenous knowledge: pioneer NGOs in India
Abstract
Background
Until recently, little attention has been paid to local innovation capacity as well as management practices and institutions developed by communities and other local actors based on their traditional knowledge. This paper doesn't focus on the results of scientific research into innovation systems, but rather on how local communities, in a network of supportive partnerships, draw knowledge for others, combine it with their own knowledge and then innovate in their local practices. Innovation, as discussed in this article, is the capacity of local stakeholders to play an active role in innovative knowledge creation in order to enhance local health practices and further environmental conservation. In this article, the innovative processes through which this capacity is created and reinforced will be defined as a process of "ethnomedicine capacity".
Methods
The field study undertaken by the first author took place in India, in the State of Tamil Nadu, over a period of four months in 2007. The data was collected through individual interviews and focus groups and was complemented by participant observations.
Results
The research highlights the innovation capacity related to ethnomedical knowledge. As seen, the integration of local and scientific knowledge is crucial to ensure the practices anchor themselves in daily practices. The networks created are clearly instrumental to enhancing the innovation capacity that allows the creation, dissemination and utilization of 'traditional' knowledge. However, these networks have evolved in very different forms and have become entities that can fit into global networks. The ways in which the social capital is enhanced at the village and network levels are thus important to understand how traditional knowledge can be used as an instrument for development and innovation.
Conclusion
The case study analyzed highlights examples of innovation systems in a developmental context. They demonstrate that networks comprised of several actors from different levels can synergistically forge linkages between local knowledge and formal sciences and generate positive and negative impacts. The positive impact is the revitalization of perceived traditions while the negative impacts pertain to the transformation of these traditions into health commodities controlled by new elites, due to unequal power relations
Life is Getting Better: Societal Evolution and Fit with Human Nature
Human society has changed much over the last centuries and this process of ‘modernization’ has profoundly affected the lives of individuals; currently we live quite different lives from those forefathers lived only five generations ago. There is difference of opinion as to whether we live better now than before and consequently there is also disagreement as to whether we should continue modernizing or rather try to slow the process down. Quality-of-life in a society can be measured by how long and happy its inhabitants live. Using these indicators I assess whether societal modernization has made life better or worse. Firstly I examine findings of present day survey research. I start with a cross-sectional analysis of 143 nations in the years 2000–2008 and find that people live longer and happier in today’s most modern societies. Secondly I examine trends in modern nations over the last decade and find that happiness and longevity have increased in most cases. Thirdly I consider the long-term and review findings from historical anthropology, which show that we lived better in the early hunter-gatherer society than in the later agrarian society. Together these data suggest that societal evolution has worked out differently for the quality of human life, first negatively, in the change from a hunter-gatherer existence to agriculture, and next positively, in the more recent transformation from an agrarian to an industrial society. We live now longer and happier than ever before
Dipoid-Specific Genome Stability Genes of S. cerevisiae: Genomic Screen Reveals Haploidization as an Escape from Persisting DNA Rearrangement Stress
Maintaining a stable genome is one of the most important tasks of every living cell and the mechanisms ensuring it are similar in all of them. The events leading to changes in DNA sequence (mutations) in diploid cells occur one to two orders of magnitude more frequently than in haploid cells. The majority of those events lead to loss of heterozygosity at the mutagenesis marker, thus diploid-specific genome stability mechanisms can be anticipated. In a new global screen for spontaneous loss of function at heterozygous forward mutagenesis marker locus, employing three different mutagenesis markers, we selected genes whose deletion causes genetic instability in diploid Saccharomyces cerevisiae cells. We have found numerous genes connected with DNA replication and repair, remodeling of chromatin, cell cycle control, stress response, and in particular the structural maintenance of chromosome complexes. We have also identified 59 uncharacterized or dubious ORFs, which show the genome instability phenotype when deleted. For one of the strongest mutators revealed in our screen, ctf18Δ/ctf18Δ the genome instability manifests as a tendency to lose the whole set of chromosomes. We postulate that this phenomenon might diminish the devastating effects of DNA rearrangements, thereby increasing the cell's chances of surviving stressful conditions. We believe that numerous new genes implicated in genome maintenance, together with newly discovered phenomenon of ploidy reduction, will help revealing novel molecular processes involved in the genome stability of diploid cells. They also provide the clues in the quest for new therapeutic targets to cure human genome instability-related diseases
Can the feedback of patient assessments, brief training, or their combination, improve the interpersonal skills of primary care physicians? A systematic review
<p>Abstract</p> <p>Background</p> <p>Improving quality of primary care is a key focus of international health policy. Current quality improvement efforts place a large focus on technical, clinical aspects of quality, but a comprehensive approach to quality improvement should also include interpersonal care. Two methods of improving the quality of interpersonal care in primary care have been proposed. One involves the feedback of patient assessments of interpersonal care to physicians, and the other involves brief training and education programmes. This study therefore reviewed the efficacy of (i) feedback of real patient assessments of interpersonal care skills, (ii) brief training focused on the improvement of interpersonal care (iii) interventions combining both (i) and (ii)</p> <p>Methods</p> <p>Systematic review of randomised controlled trials. Three electronic databases were searched (CENTRAL, Medline and Embase) and augmented by searches of the bibliographies of retrieved articles. The quality of studies was appraised and results summarised in narrative form.</p> <p>Results</p> <p>Nine studies were included (two patient based feedback studies and seven brief training studies). Of the two feedback studies, one reported a significant positive effect. Only one training study reported a significant positive effect.</p> <p>Conclusion</p> <p>There is limited evidence concerning the effects of patient based feedback. There is reasonable evidence that brief training as currently delivered is not effective, although the evidence is not definitive, due to the small number of trials and the variation in the training methods and goals. The lack of effectiveness of these methods may reflect a number of issues, such as differences in the effectiveness of the interventions in experienced practitioners and those in training, the lack of theory linking feedback to behaviour change, failure to provide sufficient training or to use a comprehensive range of behaviour change techniques. Further research into both feedback and brief training interventions is required before these interventions are routinely introduced to improve patient satisfaction with interpersonal care in primary care. The interventions to be tested in future research should consider using insights from the wider literature on communication outside primary care, might benefit from a clearer theoretical basis, and should examine the use of combined brief training and feedback.</p
- …