Monitoring enzyme secretion in tissue culture has proved challenging because to date the activity cannot be continuously measured in situ. In this Letter, we present a solution using biopolymer ...loaded photonic crystals of anodized silicon. Shifts in the optical response by proteolytic degradation of the biopolymer provide label-free sensing with unprecedented low detection limits (1 pg) and calculation of kinetic parameters. The enhancement in sensitivity relative to previous photonic crystal sensors constitutes a change in the sensing paradigm because here the entire pore space is responsive to the secreted enzyme rather than just the pore walls. In situ monitoring is demonstrated by detecting secretion of matrix metalloprotease 9 from stimulated human macrophages.
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IJS, KILJ, NUK, PNG, UL, UM
Changes in soil microbial biomass, enzyme activities, microbial community structure and nitrogen (N) dynamics resulting from organic matter amendments were determined in soils with different ...management histories to gain better understanding of the effects of long- and short-term management practices on soil microbial properties and key soil processes. Two soils that had been under either long-term organic or conventional management and that varied in microbial biomass and enzyme activity levels but had similar fertility levels were amended with organic material (dried lupin residue, Lupinus angustifolius L.) at amounts equivalent to 0, 4 and 8t dry matter lupinha−1. Microbial biomass C and N, arginine deaminase activity, fluorescein diacetate hydrolysis, dehydrogenase enzyme activity and gross N mineralisation were measured in intervals over an 81-day period. The community structure of eubacteria and actinomycetes was examined using PCR–DGGE of 16S rDNA fragments. Results suggested that no direct relationships existed between microbial community structure, enzyme activities and N mineralisation. Microbial biomass and activity changed as a result of lupin amendment whereas the microbial community structure was more strongly influenced by farm management history. The addition of 4tha−1 of lupin was sufficient to stimulate the microbial community in both soils, resulting in microbial biomass growth and increased enzyme activities and N mineralisation regardless of past management. Amendment with 8tlupinha−1 did not result in an increase proportional to the extra amount added; levels of soil microbial properties were only 1.1–1.7 times higher than in the 4tha−1 treatment. Microbial community structure differed significantly between the two soils, while no changes were detected in response to lupin amendment at either level during the short-term incubation. Correlation analyses for each treatment separately, however, revealed differences that were inconsistent with results obtained for soil biological properties suggesting that differences might exist in the structure or physiological properties of a microbial component that was not assessed in this study.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In Diabetes Mellitus the loss of capacity to regulate immunity, the reduction of pulmonary functions and the pro-thrombotic state determine the severity of COVID-19.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
IntroductionPrisoners are at risk of developing vitamin D deficiency due to their lacking exposure to sunlight. So far, there are no published studies evaluating blood levels of vitamin D in relation ...to the health status of inmates and the quality of the Italian prison system. AimTo investigate vitamin D status and its determinants in a cohort of prisoners. Subject and MethodsOne hundred and seventy-two (172) pri-son inmates (males, n=159, age 47± 11.3 years; females, n=13, age 43.91±12.18 years) of three penitentiaries in the province of Salerno. Vitamin D deficiency, insufficiency and sufficiency were respectively defined as a 25(OH)D level <20 ng/mL; from 20 to 30 ng/mL, >30 ng/mL. ResultsIn our group, Vitamin D deficiency occurs in 77.32% of the prisoners with 32.55% of the cases having severe insufficiency. Prisoners with higher BMI show lower circulating vitamin D levels (p<0.001). No significant relationship was found with the duration of detention (Pearson R: 0.01). ConclusionIn this cohort of inmates the vitamin D status is determined by BMI, but not by the duration of the detention.
Obesity and gestational diabetes mellitus (GDM) are rising worldwide. This study retrospectively evaluated the role of excessive gestational weight gain (eGWG) in women with GDM and different ...pre-pregnancy body mass indices (BMIs).
Optimal glycaemic control was defined as achieving glucose target thresholds in more than 80% of measurements. 283 women with GDM were categorized as underweight, normal weight, overweight or obese based on WHO's classification scheme. eGWG was defined as >18.0 kilograms for women who were underweight, >15.8 kilograms for those who were normal weight, >11.3 kilograms for those who were overweight and >9.0 kilograms for those who were obese. For the analysis, women were divided into two groups: normal and excessive GWG. The main outcomes measured were incidences of large/small for gestational age (LGA/SGA), macrosomia, preterm delivery, hypertensive disorders and caesarean sections (CS).
Excessive GWG was associated with higher birth weight and percentile (p<0.001), and with a higher prevalence of LGA (p<0.001), macrosomia (p=0.002) and hypertensive disorders (p=0.036). No statistical differences were found for the week of delivery, or prevalence of CS and SGA. The multivariate analysis highlighted both pre-pregnant BMI and eGWG as independent risk factors for LGA and macrosomia. Women with a pre-pregnant BMI of at least 25 and eGWG have a 5.43-fold greater risk of developing LGA (p=0.005).
When combined with an inadequate pre-pregnant BMI, eGWG acts as a "synergic risk factor" for a poor outcome. When obesity or GDM occur, an optimal GWG can guarantee a better pregnancy outcome.
Inouye et al describe the Hospital Elder Life Program, a new model of care designed to prevent functional and cognitive decline of older persons during hospitalization. Their results suggest that the ...program successfully prevents cognitive and functional decline in at-risk older patients.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Many works have been focused on the use of the base isolation to improve the dynamic response of the rigid blocks, avoiding the overturning of these systems. In this paper the effects of a mass ...damper on the rocking motion of a non-symmetric rigid block, subject to one-sine pulse type excitation, is investigated. The damper is modelled as a pendulum, hinged at the top of the block, with the mass lumped at the end. The equations of rocking motion, the uplift and the impact conditions are derived and the results are obtained by numerical integration of these equations. An extensive parametric analysis is performed, by taking as variable parameters the eccentricity of the centre of mass, the frequency and the amplitude of the excitation and the characteristics of the mass damper. Here the geometrical parameters characterizing the block are taken as fixed quantities, since the main objective of the study is understand if it is possible to find the optimal properties of the pendulum, capable to make more difficult the overturning of the body. The results show that the presence of the mass damper, if correctly designed, leads to a general improvement of the response of the system, since the overturning of the block occurs for values, of the amplitude of the base excitation, higher than those observed where no mass damper is used. Curves providing the optimum value of the characteristics of the mass damper versus the parameters characterizing the excitation, are finally obtained.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Frame structures can be coupled with external mechanical systems to improve their behaviour under external loads. Some examples of such mechanical systems are oscillating masses working as tuned mass ...dampers, dynamic mass absorbers, elasto-plastic dampers. Among the others possibilities, a rocking rigid block can be used to improve the seismic behaviour of a frame structure. In this paper a two degree of freedom model is considered representative of a general frame structure. It is coupled with a rocking rigid block through a visco-elastic device, which connects the lower part of the structure with the top of the rocking block. A Lagrangian approach is used to derive the nonlinear equation of motion that are successively solved numerically. A simulation campaign is performed to analyse the seismic behaviour of the coupled system by considering several registered earthquakes. In the analyses, the presence of rocking rigid block is assumed to be beneficial for the system if the coupling of frame structure with rocking rigid block reduces the absolute displacements and/or the inter-storey drifts. An extensive parametric analysis is performed varying the geometric characteristics of the block and the constitutive behaviour of the visco-elastic devices. The results of such analyses are presented through behaviour maps. For each of the parameters varied in the analyses, the corresponding value on the map provides ratio between displacements (or inter-storey drifts) of coupled system and of uncoupled bare frame. Such maps allow an immediate understanding of the effects of the block that has a beneficial effect when the ratio of the displacements is less than unity. Results reveal that in large ranges of the parameters’ values the rocking rigid block improves the seismic response of frame structure.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The degree of eutrophication in fresh water ecosystems may be influenced by the forms of phosphorus (P) leached from agricultural systems. Physico-chemical fractionation of P in leachate from a ...grassland soil carried out over a two year period indicated that the majority of the P loss from the Lismore soil occurred in unreactive particulate (55–76%) P forms.
31P nuclear magnetic resonance analysis of a selected leachate sample indicated that unreactive P was mainly comprised of monoester and diester forms of organic P. The presence of phosphomonoesterase (20–200 μg
p nitrophenol l
−1
h
−1) and phosphodiesterase (68 μg
bis-
p nitrophenol l
−1
h
−1) activity in leachate resulted in hydrolysis of 10–21% of total unreactive P (TUP), indicating that some of the monoesters and diesters can be eventually hydrolyzed into inorganic P forms during P transport. Enzyme hydrolysis showed that 23% of the TUP was present as labile monoester P (LMP), followed by 20% as inositol hexakisphosphate (IHP) and 14% as diesters (phospholipids and nucleic acids). The findings of this study suggest that LMP, IHP and diesters are an important component of organic P leaching from the grassland soil.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
AbstractTaking inspiration from the basic two-degree-of-freedom (2-DOF) models usually adopted to study base isolation (BI) and tuned mass damper (TMD), a unique main archetype 2-DOF model is here ...introduced to describe the behavior of general multi-degree-of-freedom (MDOF) frame systems, in which a stiffness discontinuity (disconnection), such as the one that can be identified in BI or TMD, may be inserted. With the aim to evaluate the dynamic enhancement following from such a discontinuity for the two masses of the model, two reference schemes (TMD scheme and BI scheme) are introduced and two particular mean gain parameters are associated with them. These represent the main subject of the parametric analyses presented in this work, based on variable mass and stiffness ratios. These analyses are carried out considering groups of earthquake records collected on the basis of a specific criterion (spectrum compatibility). The results of the parametric analyses are arranged by means of mean gain maps and surfaces that can be directly related to a reference response spectrum. The mean gain maps provide a description of the dynamic performance of the archetype model. In order to extend the results obtained for the archetype models to general MDOF frame systems, a specific equivalence procedure is then introduced. Using such an approach, it is possible to define values of mass and stiffness ratio for a general MDOF systems, and then to use the maps to design the characteristics of the disconnection. The results expressed by the mean gain maps have been confirmed by several simulations carried out with reference to a 6-story shear-type frame, thus showing some practical implications of the research.
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