1,005 research outputs found
Tendrescopic endeavors and other dynamics
Tendrescopic Endeavors and other Dynamics is an attempt to coalesce the ideas and skills that have been flying around my studio over the course of the last year into a single project. A trip to Storm King Art Center and ideas of modular making began a cycle of exploration into the way custom fittings could create light-weight and transportable sculptures. Developing a greater ability to digital model and create my own unique parts has been the charge that I have built this work upon. Science and the devices that facilitate scientific discovery act as the embodiment of the desire to know more about our surroundings. Specifically, at the Green Bank Observatory in West Virginia, a unique scenario of isolation enables sensitive instruments in a telescope from being interfered with. Using the form of the telescope and its contrast from its wooded surroundings as aesthetic inspirations, this isolation serves as an analogy to the mental clarity needed for me to be productive. Acknowledging the utopian past of geodesics and the ideals that spurred the utopian movements, this project aims to demonstrate how our current time, technology, and social consciousness can re-imagine utopia. Carefully fitting each of the parts together to make a greater whole, the Tendrescope aims to stretch and extend my making and being
The effect of hypoxia and work intensity on insulin resistance in type 2 diabetes
Context:Hypoxia and muscle contraction stimulate glucose transport in vitro. We have previously demonstrated that exercise and hypoxia have an additive effect on insulin sensitivity in type 2 diabetics.Objectives:Our objective was to examine the effects of three different hypoxic/exercise (Hy Ex) trials on glucose metabolism and insulin resistance in the 48 h after acute hypoxia in type 2 diabetics.Design, Participants, and Interventions:Eight male type 2 diabetics completed 60 min of hypoxic [mean (sem) O(2) = ∼14.7 (0.2)%] exercise at 90% of lactate threshold [Hy Ex(60); 49 (1) W]. Patients completed an additional two hypoxic trials of equal work, lasting 40 min [Hy Ex(40); 70 (1) W] and 20 min [Hy Ex(20); 140 (12) W].Main Outcome Measures:Glucose rate of appearance and rate of disappearance were determined using the one-compartment minimal model. Homeostasis models of insulin resistance (HOMA(IR)), fasting insulin resistance index and β-cell function (HOMA(β-cell)) were calculated at 24 and 48 h after trials.Results:Peak glucose rate of appearance was highest during Hy Ex(20) [8.89 (0.56) mg/kg · min, P < 0.05]. HOMA(IR) and fasting insulin resistance index were improved in the 24 and 48 h after Hy Ex(60) and Hy Ex(40) (P < 0.05). HOMA(IR) decreased 24 h after Hy Ex(20) (P < 0.05) and returned to baseline values at 48 h.Conclusions:Moderate-intensity exercise in hypoxia (Hy Ex(60) and Hy Ex(40)) stimulates acute- and moderate-term improvements in insulin sensitivity that were less apparent in Hy Ex(20). Results suggest that exercise duration and not total work completed has a greater influence on acute and moderate-term glucose control in type 2 diabetics
FarmBot Trackless Redesign
For this project the team PLANT3D worked along with Rory Aronson and FarmBot to generate a cheaper more user-friendly design for the FarmBot Genesis 1.3. Working with Rory and FarmBot, we as a team generated a list of design requirements and engineering specifications for the project. These requirements centered around creating a more accessible FarmBot model for the average person to be able to purchase and set up with ease. Much of this required taking the existing system and eliminating the most common problem areas. These were the track system, built using 1.5 meter aluminum extrusions and the complex interchangeable tooling system. Identifying the two main problem areas in the design allowed us to focus on potential solutions. With many potential systems looked at and analyzed the best ones to come out of the brainstorming process were a timing belt system that could exist directly on top of the raised bed and an all-in-one tool head system that could eliminate the need for constant changing of different tool heads. Several other designs were experimented with but ultimately were deemed to impractical or complex to reasonably fulfill the design requirements. Through multiple iterations of designs an ideal shape and layout of the wheel plates was developed. This design featured an edge which could reach below the edge of the raised bed and act as a hard stop from the FarmBot main gantry falling off either side of the raised bed. This also led to the design of aluminum end stops being placed along the corners of the raised bed in order to prevent the FarmBot gantry from running off of the ends of the bed. A double wheel design was implemented, not only to help improve the allowable deviations in the bed sides, but to provide a groove for the timing belt to easily pass. Along with the groove two idler pulleys were added onto the wheel plate to help in guiding the timing belt to the stepper motor pulley. The tool head was designed to take all the functionality of the different FarmBot tools and put them onto one tool head. In order to fit everything into one space the same size as one of the old tools, several of the components were replaced with higher quality sleeker alternatives. A new anti-clog water nozzle was added to replace the old plastic shower head. This nozzle also acts as a double for the weeder to save on space. The same Luer Lock and soil sensor were placed onto this tool head to maintain their functionality. By making these design changes costs of the system were significantly decreased. The combination of drive and tool system savings is almost 30%. The part count was reduced by over 65% by eliminating lots of small redundant parts. These changes also greatly reduced overall weight and complexity of the system. Testing the performance of our design showed no significant loss in function of the FarmBot. Precision remained within 2cm of targets everywhere around the raised bed. All but one of the parts of our new design are through current FarmBot vendors. The only new vendor is a plastic machining company manufacturing the delrin spacers. All the other custom parts will be waterjet cut by BigBlueSaw. The rest of the design is made from standard parts purchased through Open Builds and McMaster Carr. Moving forward this design shows that FarmBot could succeessfully operate as a more simplistic system, riding directly on top of a raised bed using only one tool head without any significant loss in precision or functionality
Fuel for the work required: a practical approach to amalgamating train-low paradigms for endurance athletes.
Using an amalgamation of previously studied "train-low" paradigms, we tested the effects of reduced carbohydrate (CHO) but high leucine availability on cell-signaling responses associated with exercise-induced regulation of mitochondrial biogenesis and muscle protein synthesis (MPS). In a repeated-measures crossover design, 11 males completed an exhaustive cycling protocol with high CHO availability before, during, and after exercise (HIGH) or alternatively, low CHO but high protein (leucine enriched) availability (LOW + LEU). Muscle glycogen was different (P < 0.05) pre-exercise (HIGH: 583 ± 158, LOW + LEU: 271 ± 85 mmol kg(-1) dw) but decreased (P < 0.05) to comparable levels at exhaustion (≈100 mmol kg(-1) dw). Despite differences (P < 0.05) in exercise capacity (HIGH: 158 ± 29, LOW + LEU: 100 ± 17 min), exercise induced (P < 0.05) comparable AMPKα2 (3-4-fold) activity, PGC-1α (13-fold), p53 (2-fold), Tfam (1.5-fold), SIRT1 (1.5-fold), Atrogin 1 (2-fold), and MuRF1 (5-fold) gene expression at 3 h post-exercise. Exhaustive exercise suppressed p70S6K activity to comparable levels immediately post-exercise (≈20 fmol min(-1) mg(-1)). Despite elevated leucine availability post-exercise, p70S6K activity remained suppressed (P < 0.05) 3 h post-exercise in LOW + LEU (28 ± 14 fmol min(-1) mg(-1)), whereas muscle glycogen resynthesis (40 mmol kg(-1) dw h(-1)) was associated with elevated (P < 0.05) p70S6K activity in HIGH (53 ± 30 fmol min(-1) mg(-1)). We conclude: (1) CHO restriction before and during exercise induces "work-efficient" mitochondrial-related cell signaling but; (2) post-exercise CHO and energy restriction maintains p70S6K activity at basal levels despite feeding leucine-enriched protein. Our data support the practical concept of "fuelling for the work required" as a potential strategy for which to amalgamate train-low paradigms into periodized training programs
The effect of different training modes on skeletal muscle microvascular density and endothelial enzymes controlling NO availability
It is becoming increasingly apparent that a high vasodilator response of the skeletal muscle microvasculature to insulin and exercise is of critical importance for adequate muscle perfusion and long-term microvascular and muscle metabolic health. Previous research has shown that a sedentary lifestyle, obesity, and ageing lead to impairments in the vasodilator response, while a physically active lifestyle keeps both microvascular density and vasodilator response high. To investigate the molecular mechanisms behind these impairments and the benefits of exercise training interventions, our laboratory has recently developed quantitative immunofluorescence microscopy methods to measure protein content of eNOS and NAD(P)Hoxidase specifically in the endothelial layer of capillaries and arterioles of human skeletal muscle. As eNOS produces NO and NAD(P)Hoxidase superoxide anions (quenching NO) we propose that the eNOS/NAD(P)Hoxidase protein ratio is a marker of vasodilator capacity. The novel methods show that endurance training (ET) and high intensity interval training (HIT) generally regarded as a time efficient alternative to ET, increase eNOS protein content and the eNOS/NADP(H) oxidase protein ratio in previously sedentary lean and obese young men. Resistance exercise training had smaller but qualitatively similar effects. Western blot data of other laboratories suggest that endurance exercise training leads to similar changes in sedentary elderly men. Future research will be required to investigate the relative importance of other sources and tissues in the balance between NO and O2- production seen by the vascular smooth muscle layer of terminal arterioles
Pig α<sub>1</sub>-Acid Glycoprotein: Characterization and First Description in Any Species as a Negative Acute Phase Protein.
The serum protein α1-acid glycoprotein (AGP), also known as orosomucoid, is generally described as an archetypical positive acute phase protein. Here, porcine AGP was identified, purified and characterized from pooled pig serum. It was found to circulate as a single chain glycoprotein having an apparent molecular weight of 43 kDa by SDS-PAGE under reducing conditions, of which approximately 17 kDa were accounted for by N-bound oligosaccharides. Those data correspond well with the properties of the protein predicted from the single porcine AGP gene (ORM1, Q29014 (UniProt)), containing 5 putative glycosylation sites. A monoclonal antibody (MAb) was produced and shown to quantitatively and specifically react with all microheterogenous forms of pig AGP as analyzed by 2-D electrophoresis. This MAb was used to develop an immunoassay (ELISA) for quantification of AGP in pig serum samples. The adult serum concentrations of pig AGP were in the range of 1-3 mg/ml in a number of conventional pig breeds while it was lower in Göttingen and Ossabaw minipigs (in the 0.3 to 0.6 mg/ml range) and higher in young (2-5 days old) conventional pigs (mean: 6.6 mg/ml). Surprisingly, pig AGP was found to behave as a negative acute phase protein during a range of experimental infections and aseptic inflammation with significant decreases in serum concentration and in hepatic ORM1 expression during the acute phase response. To our knowledge this is the first description in any species of AGP being a negative acute phase protein
A pre/post analysis of the impact of the COVID-19 pandemic on the psychosocial work environment and recovery among healthcare workers in a large university hospital in Sweden
Background: The impact of the COVID-19 pandemic on workload, mental health, and well-being of healthcare workers, and particularly those on the front-line, has received considerable attention. Design and methods: We surveyed hospital employees about their working environment during the pandemic and identified departments which were negatively affected in comparison to the pre-pandemic situation, as well as factors contributing to this. Setting and participants We surveyed all hospital employees at Sahlgrenska University Hospital, Sweden in September 2020 and compared results across departments and to the results of a large employee survey from October 2019. Results: The overall impact of the pandemic on perceived working conditions and possibility for recovery differed among departments. During the pandemic, healthcare workers working with COVID-19 patients reported poorer working environments than other employees. Factors significantly related to perception of work environment and recovery during the pandemic included worries of being infected, departmental transfer, and having insufficient access to personal protective equipment. Men reported better working conditions than women in all, but one item and higher age was related to better perceived working environment. Conclusions: Our results indicate that the pandemic differentially affects hospital departments and underscores the multifactorial nature of this topic. Contributing factors to poor perceived working environment could be addressed at times of high workload, such as during the pandemic, including providing appropriate support to managers, ensuring possibility for recovery during working hours, and acknowledging worries about infection. Young healthcare workers and staff who are relocated due to the pandemic warrant special attention
Insulin Treatment Attenuates Small Nerve Fiber Damage in Rat Model of Type 2 Diabetes
Introduction. Current clinical guidelines for management of diabetic peripheral neuropathy (DPN) emphasize good glycemic control. However, this has limited effect on prevention of DPN in type 2 diabetic (T2D) patients. This study investigates the effect of insulin treatment on development of DPN in a rat model of T2D to assess the underlying causes leading to DPN. Methods. Twelve-week-old male Sprague-Dawley rats were allocated to a normal chow diet or a 45% kcal high-fat diet. After eight weeks, the high-fat fed animals received a mild dose of streptozotocin to induce hyperglycemia. Four weeks after diabetes induction, the diabetic animals were allocated into three treatment groups receiving either no insulin or insulin-releasing implants in a high or low dose. During the 12-week treatment period, blood glucose and body weight were monitored weekly, whereas Hargreaves’ test was performed four, eight, and 12 weeks after treatment initiation. At study termination, several blood parameters, body composition, and neuropathy endpoints were assessed. Results. Insulin treatment lowered blood glucose in a dose-dependent manner. In addition, both doses of insulin lowered lipids and increased body fat percentage. High-dose insulin treatment attenuated small nerve fiber damage assessed by Hargreaves’ test and intraepidermal nerve fiber density compared to untreated diabetes and low-dose insulin; however, neuropathy was not completely prevented by tight glycemic control. Linear regression analysis revealed that glycemic status, circulating lipids, and sciatic nerve sorbitol level were all negatively associated with the small nerve fiber damage observed. Conclusion. In summary, our data suggest that high-dose insulin treatment attenuates small nerve fiber damage. Furthermore, data also indicate that both poor glycemic control and dyslipidemia are associated with disease progression. Consequently, this rat model of T2D seems to fit well with progression of DPN in humans and could be a relevant preclinical model to use in relation to research investigating treatment opportunities for DPN
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