Predominant microflora of downgraded Danish bulk tank milk

The microflora of downgraded Danish bulk tank milk was examined to identify the main causes of increased microbial counts. Seventy-five representative samples with a microbial count exceeding 3.0 x 10(4) cfu/mL were selected for a more detailed microbial examination. A total of 1237 isolates from these samples were identified. Gram-negative, oxidase-positive bacteria were found in 72% of the samples. Coliforms were found in 20% of the samples, and non-coliforms were found in 49% of the samples. Coryneforms, other gram-positive rods, Lactococcus spp., Micrococcus spp., and coagulase-negative Staphylococcus spp. were found in 28 to 53% of the samples. Bacillus spp., Enterococcus spp., Staphylococcus aureus, Streptococcus dysgalactiae, Streptococcus uberis, and yeasts were found in <25% of the samples. Additionally, the isolates were divided into 3 groups, based on the main cause of an elevated microbial count. Microorganisms primarily associated with poor hygiene dominated the microflora in 64% of the samples; bacteria also related to poor hygiene, but in addition associated with growth at low temperatures (psychrotrophic bacteria) dominated the microflora in 28% of the samples; and bacteria mainly associated with mastitis dominated the microflora in 8% of the samples. A bulk tank milk storage period of 48 h instead of 24 h did not affect the proportion of downgraded milk samples and could not be associated with a specific group of microorganisms. Further, no relationship was found between somatic cell counts and the presence of mastitis bacteria.     

Sweetness and texture perceptions in structured gelatin gels with embedded sugar rich domains

Layered and homogeneous gelatin gels with controlled rheological properties were compared for their sensory characteristics, specifically sweetness, hardness, breakdown behaviour and frothing. All gels and layers had a gelatin/water concentration of 5%. The total sugar concentration was 9% in the layered samples and 0, 9, 15 or 22.5% in the homogeneous samples. These concentrations corresponded to the concentrations in the single layers.A seven-layered sample with different sugar concentrations in the layers gave a higher early sweetness intensity than a homogeneous gel with the same mean total sugar concentration. All layered gels were similar in hardness, breakdown behaviour and frothing; for the homogenous samples, sensory hardness was decreased in samples with much sugar. These gels also fell into smaller pieces than the sugarless sample. This study shows that it is possible by controlling the sugar distribution within a sample to produce sweeter gels while the sugar content is maintained.     

Biomass production,water use and photosynthesis of Salix clones grown in a wastewater purification system

An objective of the study was to identify leaf morphophysiological characteristics indicative of high aboveground woody biomass production of Salix clones growing in the vegetation filter of a wastewater purification system. It was hypothesized, that in these extra irrigated stands, the characteristics of photosynthesis are stronger determinants of the production than the characteristics of leaf water relations. The biomass production of the clones was correlated with numerous characteristics of leaf water relations and photosynthesis. Significant correlation was found between the biomass production and the following characteristics of top foliage leaves: daily decrease in water potential, stomatal conductance, stomatal sensitivity to increase in light intensity, and hydraulic conductance (positive); daily minimum and maximum water potentials, instantaneous water use efficiency, and stomatal sensitivity to decrease in leaf water potential (negative); maximum rate of photosynthetic electron transport, chlorophyll content, and the partitioning coefficient for leaf nitrogen into bioenergetics associated with electron transport (positive). In the most productive clones, the vertical gradient (through foliage) of values of almost all the characteristics was the smallest. The biomass correlated more strongly with the characteristics of photosynthesis light stage than with the characteristics of water relations. We conclude that the characteristics of photosynthesis light stage – high maximum rate of photosynthetic electron transport, high chlorophyll content, and also flat vertical gradient (through foliage) in values of the characteristics could be the strongest indicators of high biomass production of Salix clones growing in vegetation filter.     

Potential contribution of geothermal energy to climate change adaptation: A case study of the arid and semi-arid eastern Baringo lowlands,Kenya

The impacts of recurrent droughts have increased vulnerability and reduced the adaptive capacity of the people living in arid and semi-arid lands (ASALS) of Kenya. Current interventions are short-term and curative in nature, hence unsustainable. Some of the most arid and semi-arid lands are located within the Kenyan Rift system, which has an estimated geothermal potential of about 7000 to 10,000 MWe, out of which only 200 MWe has been developed, and about 5000 MWe planned by 2030. Recent power sector reforms have built institutional structures that will accelerate development of geothermal energy. The paper analyses the potential use of geothermal energy resources in eastern Baringo lowlands between Lake Bogoria and Silali prospects, which has an estimated potential of >2700 MWe, in creating the necessary adjustments needed to adapt to the impacts of recurrent droughts by locals. Opportunities for direct and indirect uses of geothermal energy exist in climate vulnerable sectors, such as, agriculture, fisheries, water, livestock production as well as alternative income generating activities such as, tourism, micro enterprises, aloe, honey and beeswax production, fabric dyeing and others using resources sourced from within a 50 km radius. The possibility of accelerated geothermal development and proposed utilisation schemes in causing maladaptation if unsustainably implemented is also discussed. The paper draws a Lindal diagram adapted to the study area showing potential utilisation in the above sectors, and new flow diagram showing potential for cascaded use of geothermal hot water through the different processes. An estimated capacity of 100 MWt and 100 MWe can be used in the potential utilisation schemes discussed in this article to meet local adaptation and lighting needs and much less in a cascaded process. Potential barriers and possible solutions are also discussed. The study concludes that geothermal energy is a vital option for adaptation in the study area if sustainably used.     

Non-invasive assessment of magnitude and dispersion of atrial cycle length during chronic atrial fibrillation in man

AIMS: Atrial fibrillation cycle lengths can be assessed from right precordial ECG leads and the unipolar oesophageal ECG using a non-invasive method called Frequency Analysis of Fibrillatory ECG. The purpose of this report is to present the results from application of this method in a large group of patients with long-term atrial fibrillation and to examine the differences between patients with 'coarse' and 'fine' atrial fibrillation. METHODS AND RESULTS: Simultaneous 15 min recordings from V1, V2 and an oesophageal lead at a position behind the posterior atrium were obtained in 28 patients, aged 41 to 78 years, with long-term (> 1 month) atrial fibrillation. In each lead, using the time averaging technique, the QRST complexes were suppressed. Thereafter, the frequency distribution of the residual ECG was estimated by means of Fast Fourier Transform. In the 3-12 Hz range of each lead, the dominant atrial cycle length, the power maximum and the spectral width were calculated. In 26 patients (93%), frequency spectra in the 3-12 Hz range could be obtained. The dominant atrial cycle length ranged from 120 to 175 ms, mean 150+/-16 (SD) ms in V1, and from 120 to 190 ms, mean 150+/-16 in an oesophageal lead (ns). The absolute difference in the dominant atrial cycle length between V1 and the oesophageal lead was 10.4+/-7.7 ms. There was no significant difference in the dominant atrial cycle length in V1 between patients with coarse and fine atrial fibrillation. The power maximum in V1 was significantly greater in patients with coarse compared to fine atrial fibrillation (P=0.01). The spectral widths ranged from 10 to 55 ms and demonstrated significantly higher mean values in lead V2 compared to V1 (P=0.001). Compared to V1, the mean values tended to be smaller in the oesophageal lead (P=0.05). CONCLUSIONS: Using the Frequency Analysis of Fibrillatory ECG method, the dominant atrial cycle length, power maximum and spectral width can be estimated from the frequency spectra in the majority of patients with atrial fibrillation. Spatial dispersion of the dominant atrial cycle length occurs in some patients and may be an important proarrhythmic marker. The distinction between coarse and fine atrial fibrillation cannot be used as a marker of the atrial cycle length.     

Modification of margarine fats by enzymatic interesterification: Evaluation of a solid-fat-content-based exponential model with two groups of oil blends

Lipozyme TL IM-catalyzed interesterification for the modification of margarine fats was carried out in a batch reactor at 70°C with a lipase dosage of 4%. Solid fat content (SFC) was used to monitor the reaction progress. Lipase-catalyzed interesterification, which led to changes in the SFC, was assumed to be a first-order reversible reaction. Accordingly, the change in SFC vs. reaction time was described by an exponential model. The model contained three parameters, each with a particular physical or chemical meaning: (i) the initial SFC (SFC₀), (ii) the change in SFC (ΔSFC) from the initial to the equilibrium state, and (iii) the reaction rate constant value (k). SFC_o and ΔSFC were related to only the types of blends and the blend ratios. The rate constant k was related to lipase activity on a given oil blend. Evaluation of the model was carried out with two groups of oil blends, i.e., palm stearin/coconut oil in weight ratios of 90∶10, 80∶20, and 70∶30, and soybean oil/fully hydrogenated soybean oil in weight ratios of 80∶20, 65∶35, and 50∶50. Correlation coefficients higher than 0.99 between the experimental and predicted values were observed for SFC at temperatures above 30°C. The model is useful for predicting changes in the SFC during lipase-catalyzed interesterification with a selected group of oil blends. It also can be used to control the process when particular SFC values are targeted.     

Humidity sensitivity of optical structures prepared by r.f.-biased r.f. sputtering

In an attempt to produce optical structures with a lower humidity sensitivity than that of structures deposited by conventional evaporation, we used r.f.-biased r.f. sputtering for the preparation of coatings. The sensitivity was effectively reduced owing to the high density of bias-sputtered films which are subjected to controlled ion bombardment during their growth. Our experiments suggest that neither rate monitoring nor optical monitoring is necessary, at least not in the preparation of simple structures with few layers, if glow discharge sputtering processes comprising r.f. substrate biasing in diode, triode or magnetron set-ups are used to deposit the coatings.     

在减少碳足迹的道路上——Stora Enso集团减少碳足迹实例

近年来,为了人类的可持续发展和应对全球气候变暖,减少碳排放及发展低碳经济已成为全球共识。林纸产品行业在遏制气候变化方面握有先机,可持续森林和人工林管理在减缓气候变化方面发挥着重要作用。     

Change in contact temperature of finger touching on cold surfaces

This study deals with human fingers touching cold surfaces of four materials (aluminium, steel, nylon and wood) at different surface temperatures (−20°C, −15°C, −10°C, −4°C, 0°C and 2°C). Contact finger skin-surface interface temperature and subjective responses on thermal and pain sensations were determined during touching. Type of material and their surface temperature clearly affected the contact cooling of the finger. Individual variation in finger contact cooling was significant. Contact temperature limits for human fingers touching cold surfaces are suggested according to the experimental results. In addition, time to reach a critical temperature (7°C, 5°C or 0°C) when contacting a cold metallic surface is discussed.

Relevance to industry

The outcome of this experimental study supplies as a basis for the development of an ergonomics database to determine temperature limit values for cold touchable surfaces. The critical temperatures are relevant to all industries where cold surfaces cause a risk of finger contact cooling for the manual protection in the cold operations.