5,352 research outputs found
Plugged hollow shaft makes fatigue-resistant shear pin
Shear pin coupling with plugged hollow shaft provides required load capacity for shaft protection and has no groove to induce fatigue failure
Fatigue-resistant shear pin
Fatigue resistant shear pin with hollow shaft and two plug
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2,3,7,8‑Tetrachlorodibenzo‑p‑dioxin suppresses the growth of human liver cancer HepG2 cells in vitro: Involvement of cell signaling factors.
The aryl hydrocarbon receptor (AHR) is transcriptionally active in the form of a heterodimer with the AHR nuclear translocator, which then binds to the xenobiotic responsive element. AHR was originally discovered via its ligand, the polychlorinated hydrocarbon, 2,3,7,8‑tetrachlorodibenzo‑p‑dioxin (TCDD). In this study, we investigated whether TCDD regulates the growth of human liver cancer HepG2 cells in vitro. TCDD (0.1‑100 nM) was found to exert suppressive effects on the colony formation and proliferation of HepG2 cells, and stimulatory effects on the death of HepG2 cells when the cells reached subconfluence. The effects of TCDD on the HepG2 cells were abolished by culture with CH223191, an inhibitor of AHR signaling. The effects of TCDD were dependent on the concentration of serum, which contains various signaling factors. The effects of TCDD were not potentiated by culture with tumor necrosis factor‑α, which activates the signaling of nuclear factor‑κB (NF‑κB). The results of western blot analysis revealed that TCDD increased the protein levels of p53, Rb, p21, and regucalcin, which are suppressors of the growth of tumor cells. Moreover, TCDD enhanced the NF‑κB p65, β‑catenin, signal transducer and activator of transcription 3 (STAT3), Ras and Akt levels. Thus, the findings of this study indicate that TCDD may suppress liver cancer cell growth through various signaling pathways, mediated by AHR and its‑related co‑factors. Of note, the effects of TCDD were found to be potentiated by gemcitabine, which induces nuclear DNA damage in cancer cells, suggesting that their combined use may have potential as a suppressor of tumor cell growth
Concentrated burdens: how self-interest and partisanship shape opinion on opioid treatment policy
When does self-interest influence public opinion on contentious public policies? The bulk of theory in political science suggests that self-interest is only a minor force in public opinion. Using nationally representative survey data, we show how financial and spatial self-interest and partisanship all shape public opinion on opioid treatment policy. We find that a majority of respondents support a redistributive funding model for treatment programs, while treatment funded by taxation based on a community’s overdose rate is less popular. Moreover, financial self-interest cross-pressures lower-income Republicans, closing the partisan gap in support by more than half. We also experimentally test how the spatial burden of siting treatment clinics alters policy preferences. People across the political spectrum are less supportive when construction of a clinic is proposed closer to their home. These results highlight how partisanship and self-interest interact in shaping preferences on public policy with concentrated burdens.Accepted manuscrip
Some ultrastructural and physiological studies of Phycomyces Sporangiophores
Although the Phycomyces sporangiophore has been the object of numerous physiological investigations little is known of its ultrastructure or of the changes that occur within it during growth and development. This is partly due to the failure of some workers to obtain satisfactory fixation of the sporangiophore for ultrastructural investigations. Investigations were made for suitable fixation procedures which might help to elucidate the fine structure of the sporangiophore during growth and development. Using the fixation procedures developed, long microfilaments lying almost parallel to the long axis of the sporangiophore and closely associated with mitochondria were revealed. These microfilaments probably determine the path along which the mitochondria move and may account for the multistriate streaming of organelles as seen in the phase contrast microscope. Investigations for a discrete gravity receptor proved negative but did reveal an upward displacement of the large central vacuole concurrent with the development of a geotropic curvature. I was not able to find any organelle which might function as a photoreceptor. The ultrastructural changes occurring during the development of the sporangium and germination of the spores are described
A Mother\u27s Love: A Screenplay
A Mother’s Love is a sixty-eight page feature-length dramatic screenplay. The story attempts to answer the following question: How far should a mother go to ensure her child’s overall happiness and acceptance in the world? In the screenplay, Emily is the mother of Aden, a child with autism. Aden’s autistic condition is about in the middle of the autistic spectrum. When a new doctor recommends putting Aden on an experimental treatment that promises to eliminate Aden’s autistic symptoms, Emily agrees to follow the program. Although the revolutionary treatment begins to radically ease Aden’s autistic symptoms, the drug comes with severe side effects that almost kill Emily’s son. To write this screenplay, I used Celtx, a freeware pre-production software that automatically formats scene headers, descriptions and dialogue to the generally accepted screenplay format. If produced, the screenplay’s length is meant to translate into a ninety-minute live-action film. Although the screenplay and characters are not based on anyone or anything in real life, the idea of a new drug that affects a certain part of the brain in children and adults with autism is currently being discussed ins scientific circles. Although no drug has yet been produced, this screenplay plays out one what-if scenario. The screenplay is meant to analyze the possibility of a potential cure for autism. A Mother’s Love does not provide a definite answer to the main question it leaves with its readers. Instead, it is meant to open a dialogue about autism, it’s place in today’s society, and the new research into autism’s biological causes. These topics of conversation include discussions about the potential overuse of drugs to treat psychological disorders, the lack of research that goes into certain “miracle cures” and how children and adults with autism are still fighting to be accepted into mainstream society. Autism is becoming a hot button topic in the media today, and A Mother’s Love is meant to add to the current discussion
Small Firms Investment: A Search For The Motivations 1999-2002
Some twenty years ago, research was conducted by the author into the investment
motivations of a sample of small firms in the south of England. The results were
published in the International Small Business Journal 1984. This research has been
updated between 1999 and 2002. The results were surprising in the sense that little
had changed over the period.
The aim of the original 1979-1982 South Wessex Survey was to make a contribution
to what was considered at the time to be an under-researched field by examining the
motivations and weaknesses behind investment decision making. This involved
investigating 52 small firms with up to 200 employees in the South Wessex region of
the United Kingdom.
The results showed that, in the main, small firms actually chose to ignore, and even
avoid, certain opportunities to reach the highest attainable return on investment,
indicating endemic investment weaknesses within the small engineering firm.
For example, the sample firms had concentrated on their main products over the years
for various reasons, but tradition as opposed to strategy was a principal explanation.
Hardly any firms had considered movement into new fields, and related
diversification was not popular being regarded as risky rather than risk spreading.
The impression was that diversification could have been at least as beneficial as the
activity currently engaged in which was producing sub-optimum results.
Some firms argued that diversification, and even related diversification, was
impracticable.
In output determination, flexibility is essential. Yet 46% of the firms fixed output by
allocating quotas which would be retained for some time until events dictated
otherwise. Only 27% were scheduling output in response to market forces suggesting
reasonable degrees of flexibility. But perhaps most striking was another 27% actually
employing constant output policies. Current and expected demand, as measured by
length of order books were fundamental determinants of output levels, whilst labour
availability and excess capacity acted as major influences. As far as output
constraints were concerned, inadequate plant capacity predominated with rising costs
of production second. The results indicated that very rarely did firms raise or lower
output in the shorter term in a conscious attempt to optimise sales, profits or costs.
It emerged that the principal goal of 21% of the firms was satisfactory profit.
Subsidiary policies tended to be rather more individual, e.g. safety, but two clear aims
repeated themselves: satisfactory profits and survival. Key personnel gave specific
reasons for adopting their policies. Several claimed that satisfactory profits and
survival were the only real goals for small firms especially during recessionary
economic conditions. But policies did seem to be the result of historical or traditional
decision making, and once a firm had adopted a goal this would be retained and only
amended when events dictated.Flexibility of strategy was not apparent. From this finding it seemed clear that a
flexible policy could well have increased profits, because if profits had not improved
then the policy could easily have been changed.
Since firms considered survival either second to satisfactory profits in the hierarchy of
objectives, or as one of the foundations for profitability, the signs were that firms
were simply aiming to survive. It was possible that survival could have been the
critical fundamental objective since many firms regarded this as a barometer of
success.
There were other factors that were equally worrying, and these are now considered in
parallel with the 1999-2002 follow up study
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