Reducing Livestock Losses To Toxic Plants

12 pp., 1 tablePoisonous plants are among the most significant causes of economic loss sustained each year by the livestock industry. This publication gives background information and dispels myths about poisonous plants. It will help producers diagnose problems and differentiate poisoning from infectious disease. This publication contains a 7-page appendix of poisonous Texas plants and the symptoms they cause in livestock

Characterising the effects of in vitro mechanical stimulation on morphogenesis of developing limb explants

AbstractMechanical forces due to fetal movements play an important role in joint shape morphogenesis, and abnormalities of the joints relating to abnormal fetal movements can have long-term health implications. While mechanical stimulation during development has been shown to be important for joint shape, the relationship between the quantity of mechanical stimulation and the growth and shape change of developing cartilage has not been quantified. In this study, we culture embryonic chick limb explants in vitro in order to reveal how the magnitude of applied movement affects key aspects of the developing joint shape. We hypothesise that joint shape is affected by movement magnitude in a dose-dependent manner, and that a movement regime most representative of physiological fetal movements will promote characteristics of normal shape development. Chick hindlimbs harvested at seven days of incubation were cultured for six days, under either static conditions or one of three different dynamic movement regimes, then assessed for joint shape, cell survival and proliferation. We demonstrate that a physiological magnitude of movement in vitro promotes the most normal progression of joint morphogenesis, and that either under-stimulation or over-stimulation has detrimental effects. Providing insight into the optimal level of mechanical stimulation for cartilage growth and morphogenesis is pertinent to gaining a greater understanding of the etiology of conditions such as developmental dysplasia of the hip, and is also valuable for cartilage tissue engineering

Reducing Livestock Losses To Toxic Plants

12 pp., 1 tablePoisonous plants are among the most significant causes of economic loss sustained each year by the livestock industry. This publication gives background information and dispels myths about poisonous plants. It will help producers diagnose problems and differentiate poisoning from infectious disease. This publication contains a 7-page appendix of poisonous Texas plants and the symptoms they cause in livestock

Stigma as a fundamental hindrance to the United States opioid overdose crisis response.

Alexander Tsai and co-authors discuss the role of stigma in responses to the US opioid crisis

Crystallization diagram for antisolvent crystallization of lactose : using design of experiments to investigate continuous mixing- induced supersaturation

This study investigates the effects of key process parameters of continuous mixing-induced supersaturation on the antisolvent crystallization of lactose using D-optimal Design of Experiments (DoE). Aqueous solutions of lactose were mixed isothermally with antisolvents using a concentric capillary mixer. Process parameters investigated were the choice of antisolvent (acetone or isopropanol), concentration of lactose solution, total mass flow rate, and the ratio of mass flow rates of lactose solution and antisolvent. Using a D-optimal DoE a statistically significant sample set was chosen to explore and quantify the effects of these parameters. The responses measured were the solid state of the lactose crystallized, induction time, solid yield and particle size. Mixtures of α-lactose monohydrate and β-lactose were crystallized under most conditions with β-lactose content increasing with increasing amount of antisolvent. Pure α-lactose monohydrate was crystallized using acetone as the antisolvent, with mass flow ratios near 1:1, and near saturated solutions of lactose. A higher resolution DoE was adopted for acetone and was processed using multivariate methods to obtain a crystallization diagram of lactose. The model was used to create an optimized process to produce α-lactose monohydrate and predicted results agreed well with those obtained experimentally, validating the model. The solid state of lactose, induction time, and solid yield were accurately predicted

Modelling chemistry and biology after implantation of a drug-eluting stent. Part I: Drug transport

Drug-eluting stents have been used widely to prevent restenosis of arteries following percutaneous balloon angioplasty. Mathematical modelling plays an important role in optimising the design of these stents to maximise their efficiency. When designing a drug-eluting stent system, we expect to have a sufficient amount of drug being released into the artery wall for a sufficient period to prevent restenosis. In this paper, a simple model is considered to provide an elementary description of drug release into artery tissue from an implanted stent. From the model, we identified a parameter regime to optimise the system when preparing the polymer coating. The model provides some useful order of magnitude estimates for the key quantities of interest. From the model, we can identify the time scales over which the drug traverses the artery wall and empties from the polymer coating, as well as obtain approximate formulae for the total amount of drug in the artery tissue and the fraction of drug that has released from the polymer. The model was evaluated by comparing to in-vivo experimental data and good agreement was found

Dynamics of Sleep-Wake Transitions During Sleep

We study the dynamics of the awakening during the night for healthy subjects and find that the wake and the sleep periods exhibit completely different behavior: the durations of wake periods are characterized by a scale-free power-law distribution, while the durations of sleep periods have an exponential distribution with a characteristic time scale. We find that the characteristic time scale of sleep periods changes throughout the night. In contrast, there is no measurable variation in the power-law behavior for the durations of wake periods. We develop a stochastic model which agrees with the data and suggests that the difference in the dynamics of sleep and wake states arises from the constraints on the number of microstates in the sleep-wake system.Comment: Final form with some small corrections. To be published in Europhysics Letters, vol. 57, issue no. 5, 1 March 2002, pp. 625-63

Usefulness of electroanatomical mapping during transseptal endocardial left ventricular lead implantation

AimFailure rate to implant left ventricular (LV) lead transvenously is 4-8% in cardiac resynchronization therapy (CRT) patients. Epicardial lead placement is an alternative method and if not applicable case reports and small series showed the feasibility of endocardial LV lead implantation. Electroanatomical mapping might be a useful tool to guide this procedure.Methods and resultsFour patients had undergone endocardial LV lead implantation after unsuccessful transvenous implantation or epicardial LV lead dysfunction using the transseptal approach. Electroanatomical mapping was used to mark the location of the transseptal puncture. This location point guided the mapping catheter from the subclavian access and facilitated positioning of the LV lead at the adjacent latest activation area of the left ventricle detected by activation mapping. Endocardial active fixation LV leads were successfully implanted in all patients with stable electrical parameters immediately after implantation and over a mean follow-up of 18.3 months (lead impedance 520 +/- 177 vs. 439 +/- 119 Omega and pacing threshold 0.8 +/- 0.2 V, 0.5 ms vs. 0.6 +/- 0.1 V, 0.5 ms, respectively). Patients were maintained on anticoagulation therapy with a target international normalized ratio of 3.5-4.5 and did not show any thromboembolic, haemorrhagic events, or infection. Echocardiography showed significant improvement of LV systolic function with marked improvement of the functional status.ConclusionsElectroanatomical mapping is a useful technical tool to guide endocardial LV lead implantation. It helps to identify the location of the transseptal puncture and the use of activation mapping might facilitate location of the optimal lead positions during CRT

Microscopic Optical Projection Tomography In Vivo

We describe a versatile optical projection tomography system for rapid three-dimensional imaging of microscopic specimens in vivo. Our tomographic setup eliminates the in xy and z strongly asymmetric resolution, resulting from optical sectioning in conventional confocal microscopy. It allows for robust, high resolution fluorescence as well as absorption imaging of live transparent invertebrate animals such as C. elegans. This system offers considerable advantages over currently available methods when imaging dynamic developmental processes and animal ageing; it permits monitoring of spatio-temporal gene expression and anatomical alterations with single-cell resolution, it utilizes both fluorescence and absorption as a source of contrast, and is easily adaptable for a range of small model organisms