Federal Crop Insurance is Part of Farm Safety Net for Maryland Potato Producers

Gives overview of the qualifications for crop insurance on potatoes in Marylan

Effect of Market Channel, Farm Scale, and Years in Production on Mid-Atlantic Vegetable Producers\u27 Knowledge and Implementation of Good Agricultural Practices

Foodborne illnesses associated with fresh produce have dramatically increased within the last decade. Good Agricultural Practices (GAP) were developed to address potential sources of pre-harvest microbial contamination, but certification remains low. The majority of mid-Atlantic vegetable farms are fresh market, but limited information is available about what on-farm production practices are being utilized to mitigate food safety risks. Our goal was to assess Maryland and Delaware vegetable producers\u27 understanding and implementation of GAP. An electronic survey on pre-harvest production practices was administered at commercial grower meetings in 2010 and 2013. A total of 313 surveys were analyzed, and Probit regression was used to estimate the average marginal effects of farm scale, years in production and market channel on the probability of using different on-farm food safety practices. Generally, food safety practices did not differ across farm scale or years in production. However, market channel did influence a grower\u27s decision to implement some food safety practices. Growers who marketed their produce primarily through wholesale channels were more likely to: have written policies for how they grew and handled their produce, test their irrigation water at least once a year for microbial contamination, or be GAP-certified. Economic constraints were not reported as the primary obstacle for GAP implementation in either survey. While more research is needed to better understand how market channel influences decision-making activities including on-farm food safety practices, this study highlights the complexity of the issue and the need for GAP educational programs to expand beyond a one-size-fits-all approach

The Atacama Cosmology Telescope: CMB Polarization at 200<ℓ<9000200<\ell<9000

We report on measurements of the cosmic microwave background (CMB) and celestial polarization at 146 GHz made with the Atacama Cosmology Telescope Polarimeter (ACTPol) in its first three months of observing. Four regions of sky covering a total of 270 square degrees were mapped with an angular resolution of $1.3'$. The map noise levels in the four regions are between 11 and 17 $\mu$K-arcmin. We present TT, TE, EE, TB, EB, and BB power spectra from three of these regions. The observed E-mode polarization power spectrum, displaying six acoustic peaks in the range $200<\ell<3000$, is an excellent fit to the prediction of the best-fit cosmological models from WMAP9+ACT and Planck data. The polarization power spectrum, which mainly reflects primordial plasma velocity perturbations, provides an independent determination of cosmological parameters consistent with those based on the temperature power spectrum, which results mostly from primordial density perturbations. We find that without masking any point sources in the EE data at $\ell<9000$, the Poisson tail of the EE power spectrum due to polarized point sources has an amplitude less than $2.4$ $\mu$K$^2$ at $\ell = 3000$ at 95\% confidence. Finally, we report that the Crab Nebula, an important polarization calibration source at microwave frequencies, has 8.7\% polarization with an angle of $150.7^\circ \pm 0.6^\circ$ when smoothed with a $5'$ Gaussian beam.Comment: 16 pages, 15 figures, 5 table

Cytochrome P450 Reductase: A Harbinger of Diffusible Reduced Oxygen Species

The bi-enzymatic system of cytochrome P450 (CYP, a hemoprotein) and cytochrome P450 reductase (CPR, a diflavoenzyme) mediate the redox metabolism of diverse indigenous and xenobiotic molecules in various cellular and organ systems, using oxygen and NADPH. Curiously, when a 1:1 ratio is seen to be optimal for metabolism, the ubiquitous CYP:CPR distribution ratio is 10 to 100:1 or higher. Further, the NADPH equivalents consumed in these in vitro or in situ assemblies usually far exceeded the amount of substrate metabolized. We aimed to find the rationale to explain for these two oddities. We report here that CPR is capable of activating molecular oxygen on its own merit, generating diffusible reduced oxygen species (DROS). Also, in the first instance for a flavoprotein, CPR is shown to deplete peroxide via diffusible radical mediated process, thereby leading to the formation of water (but without significant evolution of oxygen). We also quantitatively demonstrate that the rate of oxygen activation and peroxide depletion by CPR accounts for the major reactivity in the CYP+CPR mixture. We show unambiguously that CPR is able to regulate the concentration of diffusible reduced oxygen species in the reaction milieu. These findings point out that CPR mediated processes are bound to be energetically ‘wasteful ’ and potentially ‘hazardous ’ owing to the unavoidable nature of the CPR to generate and deplete DROS. Hence, we can understand that CPR is distributed at low densities in cells. Some of the activities that were primarily attributed to the heme-center of CYP are now established to be a facet of the flavins of CPR. The current approach of modeling drugs to minimize ‘‘uncoupling’ ’ o

Effect of storage time and temperature change on the dimensional stability of polyvinyl siloxane and polyether impression materials: An in vitro study

Background: Synthetic elastomers such as polyvinyl siloxane and polyether are the most commonly used impression materials. The accuracy and dimensional stability of these materials are influenced by the temperature, humidity, and storage time. Aim: The aim of this study was to assess the effect of storage time and temperature on the dimensional stability of polyvinyl siloxane and polyether impression materials. Materials and Methods: A stainless steel die was used to prepare the molds from three brands of polyvinyl siloxane (Elite HD, Express STD, Aquasil) and one brand of polyether (Impregnum F) impression materials. The samples were stored at five different temperatures (10°C, 180°C, 280°C, 350°C, and 450°C) for 24, 48, and 72 h, respectively. The linear change in the dimension of the materials were recorded and analyzed. Results: When stored at 280°C and 450°C, polyvinyl siloxane did not show any significant dimensional change in 24, 48, and 72 h when compared to control samples. At 10°C, significant dimensional change was noted in 24 h (P = 0.00) and at 180°C, significant change in the dimension was noted in 24 and 48 h (P = 0.01,P= 0.00, respectively). At 350°C, polyvinyl siloxane showed expansion in 24 and 48 h (P = 0.00,P= 0.04, respectively) whereas no further change occurred in 72 h. Significant changes in the dimensional stability were noted for polyether at all the five storage temperatures (10°C, 180°C, 280°C, 350°C, and 450°C) when compared to control samples. Conclusion: All the three brands of polyvinyl siloxane and the one brand of polyether tested showed statistically significant dimensional changes in 10°C, 180°C, 350°C, and 450°C, whereas at 280°C, all the tested materials showed no significant changes. Most of these changes occurred within 24 h, with very little changes occurring in 48 and 72 h

The effect of a radical scavenger in CPR mediated peroxide depletion.

<p>The effect of a radical scavenger in CPR mediated peroxide depletion.</p

Tracing of oxygen evolution in peroxide depletion reactions.

<p>Tracing of oxygen evolution in peroxide depletion reactions.</p

Molecular mechanisms of oxygen activation and peroxide depletion by CPR.

<p><b><i>5a. Activation of oxygen by reduced CPR to generate DROS. 5b: Probable flavin-based mechanistic route for degradation of peroxide</i></b>.</p