The Need for Higher Minimum Staffing Standards in U.S. Nursing Homes.

Many U.S. nursing homes have serious quality problems, in part, because of inadequate levels of nurse staffing. This commentary focuses on two issues. First, there is a need for higher minimum nurse staffing standards for U.S. nursing homes based on multiple research studies showing a positive relationship between nursing home quality and staffing and the benefits of implementing higher minimum staffing standards. Studies have identified the minimum staffing levels necessary to provide care consistent with the federal regulations, but many U.S. facilities have dangerously low staffing. Second, the barriers to staffing reform are discussed. These include economic concerns about costs and a focus on financial incentives. The enforcement of existing staffing standards has been weak, and strong nursing home industry political opposition has limited efforts to establish higher standards. Researchers should study the ways to improve staffing standards and new payment, regulatory, and political strategies to improve nursing home staffing and quality

Effect of Co doping and hydrostatic pressure on SrFe2As2

We report a pressure study on electron doped SrFe$_{2-x}$Co$_x$As$_2$ by electrical-resistivity ($\rho$) and magnetic-susceptibility ($\chi$) experiments. Application of either external pressure or Co substitution rapidly suppresses the spin-density wave ordering of the Fe moments and induces superconductivity in SrFe$_2$As$_2$. At $x=0.2$ the broad superconducting (SC) dome in the $T-p$ phase diagram exhibits its maximum $T_{c,{\rm max}}=20$ K at a pressure of only $p_{\rm max}\approx 0.75$ GPa. In SrFe$_{1.5}$Co$_{0.5}$As$_2$ no superconductivity is observed anymore up to 2.8 GPa. Upon increasing the Co concentration the maximum of the SC dome shifts toward lower pressure accompanied by a decrease in the value of $T_{c,{\rm max}}$. Even though, superconductivity is induced by both tuning methods, Co substitution leads to a much more robust SC state. Our study evidences that in SrFe$_{2-x}$Co$_x$As$_2$ both, the effect of pressure and Co-substitution, have to be considered in order to understand the SC phase-diagram and further attests the close relationship of SrFe$_2$As$_2$ and its sister compound BaFe$_2$As$_2$.Comment: 6 pages, 6 figure

Effects pesticides pose upon nitrogen fixation and nodulation by dry bean (Phaselous vulgaris L. 'Bonus')

Call number: LD2668 .T4 1986 S36Master of ScienceHorticulture, Forestry, and Recreation Resource

Optimization of the spatial distribution of a therapeutic pressurized aerosol (PIPAC): an ex-vivo study

For a long time, PM has been considered to be a terminal clinical condition. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is an innovative therapeutic approach with the target to become a curative treatment. The chemotherapeutic drugs are not delivered anymore into the abdominal cavity by conventional lavage, but administered by means of a pressurized, chemotherapeutic drug containing aerosol. The objective is to achieve a homogeneous drug distribution within the abdominal cavity. Through the gaseous propagation of the chemotherapeutic drugs, every region, regardless of its proximity or distance to the nozzle of the nebulizer in the laparoscopic setting, is covered sufficiently. This is not attainable with conventional lavage, where the low abdominal regions are treated sufficiently due to gravitational forces, while the upper regions are less covered, resulting in ineffective cancer treatment, as not all tumor nodules are caught. In the past, various in vivo, ex vivo and postmortem swine experiments have been made to describe and improve the distribution pattern of an injected aerosol and the penetration depth into the serosal tissue. However, theoretical considerations regarding homogenous drug distribution via aerosolized administration did not match with actual results. Drug propagation was found out to be heterogeneous. All presented models suffer from different limitations, such as difficult reproducibility of results, extensive costs, and high discrepancies between anatomical conditions and model setup. Therefore, in this dissertation, a new ex vivo preclinical model, the inverted bovine urinary bladder, has been introduced. Advantages of the inverted bovine urinary bladder include simple handling, cost effectiveness, effect evaluation of various substances both on the mucosa and the serosa, integration of the physico-chemical characteristics of the operational environment, and proximity to the abdominal anatomical conditions. Additionally, so far, no model is able to cover the transient behavior of spray propagation. Therefore, a first dynamic experimental model, the Thermographic Imaging, has been established to describe the aerosol propagation within a model box during the injection period in real time. The presented Thermographic Imaging model is able to characterize the spraying behavior of the inserted different nebulizers and the aerosol propagation behavior during injection phase, but due to technical restrictions is not applicable to the sedimentation process of the aerosol during the exposure period. A further focus of this dissertation is the implementation of a series of experiments, in which aerosols are created via two different nebulizers (Capnopen® and Prototype4) and and their distribution/penetration depth pattern is evaluated in these new established models. First, a visual-qualitative proof of drug distribution in all parts of the bladder was conducted, observing the effect of injected dye methylene blue and ICG. This was enhanced with penetration depth measurements of injected DAPI in three predefined regions within the urinary bladder. Obtained data revealed relevant differences not only between the three different regions, but also between the investigated two Capnopen® types. The Prototype4 achieved superior penetration depth in total and a more homogenous distribution. In a third step, cisplatin, one of the chemotherapeutic drugs used in PIPAC technology, was aerosolized and tissue concentration in the same three locations measured. Obtained data confirm the findings of DAPI penetration depth measurements. These series of experiments show impressively the need of optimizing both the technical, physical, and pharmacodynamic characteristics of the injected aerosol and the distribution pattern. The aerosol characteristics of the Prototype4 are superior in many ways. The combination of improved injection, more homogenous droplet size range, higher and more equally distributed penetration depth values and tissue concentration underlines the achieved aerosol improvement. The inverted bovine urinary bladder turns out to be a valid model for the evaluation of the distribution pattern and penetration depth in the serosal tissue. In the future, these obtained promising results from the preclinical models should be transferred to the clinical operational setting

Enhancement of the upper critical field in codoped iron-arsenic high-temperature superconductors

We present the first study of codoped iron-arsenide superconductors of the 122 family (Sr/Ba)_(1-x)K_xFe_(2-y)Co_yAs_2 with the purpose to increase the upper critical field H_c2 compared to single doped (Sr/Ba)Fe_2As_2 materials. H_c2 was investigated by measuring the magnetoresistance in high pulsed magnetic fields up to 64 T. We find, that H_c2 extrapolated to T = 0 is indeed enhanced significantly to ~ 90 T for polycrystalline samples of Ba_0.55K_0.45Fe_1.95Co_0.05As_2 compared to ~75 T for Ba_0.55K_0.45Fe_2As_2 and BaFe_1.8Co_0.2As_2 single crystals. Codoping thus is a promising way for the systematic optimization of iron-arsenic based superconductors for magnetic-field and high-current applications.Comment: 7 pages, 5 figures, submitted to Journal of Applied Physic

Competition of local-moment ferromagnetism and superconductivity in Co-substituted EuFe2As2

In contrast to SrFe2As2, where only the iron possesses a magnetic moment, in EuFe2As2 an additional large, local magnetic moment is carried by Eu2+. Like SrFe2As2, EuFe2As2 exhibits a spin-density wave transition at high temperatures, but in addition the magnetic moments of the Eu2+ order at around 20 K. The interplay of pressure-induced superconductivity and the Eu2+ order leads to a behavior which is reminiscent of re-entrant superconductivity as it was observed, for example, in the ternary Chevrel phases or in the rare-earth nickel borocarbides. Here, we study the delicate interplay of the ordering of the Eu2+ moments and superconductivity in EuFe1.9Co0.1As2, where application of external pressure makes it possible to sensitively tune the ratio of the magnetic (T_C) and the superconducting (T_{c,onset}) critical temperatures. We find that superconductivity disappears once T_C > T_{c,onset}.Comment: 4 pages, 4 figures, submitted to the proceedings of SCES201

Microscopic magnetic modeling for the SS=1/2 alternating chain compounds Na3_3Cu2_2SbO6_6 and Na2_2Cu2_2TeO6_6

The spin-1/2 alternating Heisenberg chain system Na$_3$Cu$_2$SbO$_6$ features two relevant exchange couplings: $J_{1a}$ within the structural Cu$_2$O$_6$ dimers and $J_{1b}$ between the dimers. Motivated by the controversially discussed nature of $J_{1a}$, we perform extensive density-functional-theory (DFT) calculations, including DFT+$U$ and hybrid functionals. Fits to the experimental magnetic susceptibility using high-temperature series expansions and quantum Monte Carlo simulations yield the optimal parameters $J_{1a}$ = $-$217 K and $J_{1b}$ = 174 K with the alternation ratio $\alpha = J_{1a}/J_{1b} \simeq$ $-$1.25. For the closely related system Na$_2$Cu$_2$TeO$_6$, DFT yields substantially enhanced $J_{1b}$, but weaker $J_{1a}$. The comparative analysis renders the buckling of the chains as the key parameter altering the magnetic coupling regime. Numerical simulation of the dispersion relations of the alternating chain model clarify why both antiferromagnetic and ferrromagnetic $J_{1a}$ can reproduce the experimental magnetic susceptibility data.Comment: published version: 11 pages, 8 figures, 5 tables + Supplemental materia