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Analysis of the Distribution Influence of the Density of Cost-forming Factors on Results of the LCCA Calculations

Abstract

The paper evaluates the relationship between the selection of the probability density function and the construction price, and the price of the building's life cycle, in relation to the deterministic cost estimate in terms of the minimum, mean, and maximum. The deterministic cost estimates were made based on the minimum, mean, and maximum prices: labor rates, indirect costs, profit, and the cost of equipment and materials. The net construction prices received were given different probability density distributions based on the minimum, mean, and maximum values. Twelve kinds of probability distributions were used: triangular, normal, lognormal, beta pert, gamma, beta, exponential, Laplace, Cauchy, Gumbel, Rayleigh, and uniform. The results of calculations with the event probability from 5 to 95% were subjected to the statistical comparative analysis. The dependencies between the results of calculations were determined, for which different probability density distributions of price factors were assumed. A certain price level was assigned to specific distributions in 6 groups based on the t-test. It was shown that each of the distributions analyzed is suitable for use, however, it has consequences in the form of a final result. The lowest final price is obtained using the gamma distribution, the highest is obtained by the beta distribution, beta pert, normal, and uniform.

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Violence indicators in Quebrada de Humahuaca, Jujuy, Argentina: The Regional Development Period from a regional perspective

Abstract

Quebrada de Humahuaca (Jujuy, Argentina) has been extensively studied by archaeologists. Studies have been focused mainly on the Late Regional Development Period (1250-1430 AD), which has been defined as a time of social conflict. In this paper we present bioarchaeological evidence of interpersonal violence related trauma found in populations of the region. A sample of 153 skulls from three sites of Quebrada de Humahuaca: Los Amarillos, La Huerta and Yacoraite, were analyzed, differentiating antemortem and perimortem fractures, cut marks as well as the presence of trophy skulls. The results were subjected to nonparametric statistical tests, in order to assess inter-site level differences, sex and age distribution. Bioarchaeological analysis determined a high frequency of interpersonal violence related trauma. Most registered injuries belonged to the antemortem type, demonstrating that the individuals of those events that had generated said cranial trauma had managed to survive. Interpersonal violence affected both men and women the same, registering no differences in neither sex nor age group, however evidence of trauma varied geographically from site to site. Statistical calculations reveal that the Yacoraite site is where the highest frequency of trauma was found, while La Huerta is where the highest level of trophy skulls was registered

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Impact of a Wide Range of Teat Lengths on Udder Healt h and Milking Time in Holstein Cows

Abstract

The objective of our experiment was to evaluate the impact of teat length on milk yield, actual milking time (AMT), milk conductivity (MC), somatic cell count (SCC) and mastitis incidence during lactation. The effect of teat length was evaluated as the occurrence of non-ideal teats (NIT; shorter than 40 mm or longer than 60 mm) at udder level and as the average length of teats on udder (ALTU). The experiment was conducted on 59 dairy cows of Holstein breed. SAS 9.3 was used for statistical calculation. There were great variances in teat length (22–96 mm) and in the rear/front teat ratio (0.8). Only 33% of the tested cows had optimal length of all teats. No evidence for a negative impact of NIT on udder health was found. ALTU showed a statistically significant effect on AMT and SCC (P < 0.05). Cows in the group of udders with short teats showed the worst results for SCC (P < 0.05) and MC. Udders with short teats showed the fastest AMT (6.78 min; P < 0.05) compared to udders with medium and long teats (7.36 min; P < 0.05 and 7.55 min; P < 0.05, respectively). Our results show that while using an udder friendly milking system, the effect of teat length on udder health could be negligible.

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Effect of Single and Multiple Pregnancies and Calf Sex on Parturition Process and Perinatal Mortality
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Imaging in nasopharyngeal carcinoma: the value of 18-Florine Fluorodeoxyglucose PET/CT in comparison to conventional imaging modalities CT and MRI

Imaging in nasopharyngeal carcinoma: the value of 18-Florine Fluorodeoxyglucose PET/CT in comparison to conventional imaging modalities CT and MRI

Background. The aim of the study was to evaluate the clinical usefulness of 18F Fluorodeoxyglucose (FDG) positron emission tomography / computed tomography (PET/CT) in the management of nasopharyngeal carcinoma (NPC) in comparison to conventional imaging modalities.

Methods. This retrospective study was done at Ospedale Niguarda, Milan, Italy. Data were acquired from 24 NPC patients between May 2003 and December 2006. They had FDG PET/CT and CT or MRI during the initial diagnosis and at follow-up. Each finding was tabulated and compared with tissue biopsy at diagnosis and clinical status during the follow up after the therapy. A statistical calculation was done to derive the value of each modality.

Results. The sensitivity and accuracy of PET/CT and CT/MRI were equally high at diagnosis. At the follow up, a negative PET/CT finding suggested a complete remission with sensitivity and negative predictive value of 100%.

Conclusions. 18F FDG PET/CT is a potential modality to be utilized in following up NPC patients for evaluating a response to therapy.

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Longevity of Cows Depending on their First Lactation Yield and Herd Production Level

Abstract

The effect of first lactation yield and herd production level on longevity was studied using data from the SYMLEK database on 12045 Polish Holstein-Friesian cows in 1371 farms from the active population in Pomerania and Kujawy. The cows first calved in 2008 and were used or disposed from the herds by the end of 2015. FREQ, GLM and CORR procedures from the SAS package were used in the statistical calculations. The optimum level of first lactation milk from the viewpoint of longevity varies according to herd production level, which serves as a measure of the quality of rearing conditions. If the living conditions are not adapted to the high milk production of first calvers, there is a possibility that their productive life will be shortened and number of calvings decreased. The percentage of voluntary culling decisions by the breeder, which included the sale for further breeding, low milk yield and old age, averaged 9% and decreased with increasing herd production level from 16% to around 6%. The main reason for culling was infertility (around 40% on average). Culling due to infertility was particularly common among the cows which produced more than 11000 kg milk as first calvers.

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The Relationship between Body Condition and Milk Composition in Dairy Goats

Abstract

A total of 46 Swiss alpine does were examined. We analysed the composition of the milk and evaluated the body condition of the animals (BCS: 0.5 to 4.5 scale) on the same day in the last third of lactation. Goats were grouped according to their body condition for statistical calculations. We found that there was a statistically detectable relationship between body condition and milk composition of the goats. Together with the increase of BCS, the fat, protein and mineral contents in the milk increased as well. Significantly more fat, protein and mineral contents were found in the milk (6.01%;3.55%; 0,98%) in case of the well-conditioned (BCS 3.5) animals than in the thin ones (BCS 1.5-2) (4.56%, 3.11%, 0.77%) (P<5%). The concentration of milk sugar was similar between thin and better conditioned groups of animals, so the body condition did not affect these values. The importance of our study is that, the high fat and protein content of milk increases the yield of dairy products. If the animals can produce milk that has higher fat and protein content, than we can produce more dairy products that will bring more economic benefits. The aim of our study was to evaluate the effects of body condition on milk yield and quality (milk composition) in dairy goats.

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Dry Period Length as Related to Milk Yield and SCC During the First Month of Subsequent Lactation

Abstract

Analysis was made of the effect of dry period length in primiparous and multiparous cows on daily milk yield during the first month of subsequent lactation and on milk somatic cell count (SCC) on the basis of the information about the test-day milkings of 59 138 cows. The GLM and FREQ procedures of the SAS package were used in the statistical calculations. Dry period length in the primiparous and multiparous cows had a significant effect (P≤0.01) on daily milk yield and udder health, determined based on SCC. In terms of milk yield, the most favourable dry period would be 51-70 days for both primiparous and multiparous cows. Depending on udder health, a dry period of 51-90 days can be suggested. Shorter dry periods had more undesirable effects than longer dry periods. Excessively shortened dry period (≤10 days) caused the daily milk yield to decrease by 17% in primiparous and by 13% in multiparous cows while increasing the risk of clinical changes of the cow’s udder, regardless of age. The proportion of milk samples that showed evidence of clinical mastitis also increased when the dry period was excessively long (>90 days), especially in multiparous cows.

Open access
Effect of Age at First Calving on First Lactation Milk Yield, Lifetime Milk Production And Longevity of Cows

Abstract

The objective of the study was to analyse the effect of age at first calving (AFC) on first lactation milk yield, lifetime milk production and longevity of dairy cows. The study used SYMLEK data on the milk yield and culling of 111 857 Polish Holstein-Friesian cows from the active population in Pomerania and Kujawy, Poland. The cows first calved during 2000–2009 and were used or removed from the herds until the end of 2015. For each cow, calculations were made of first lactation milk yield, lifetime milk production, first lactation milk yield per milking day, lifetime milk production per day, as well as the lifespan (length of productive life, duration of rearing) and number of calvings. Based on the age at first calving (duration of the rearing period), the cows were grouped as follows: ≤22, 22.1–24.0, 24.1–26.0, 26.1–28.0, 28.1–30.0, 30.1–32.0 and >32 months. The GLM, CORR PEARSON and FREQ procedures from the SAS package were used in the statistical calculations. Considering first lactation milk yield, lifetime milk production and longevity, it is recommended that the cows should be first milked between 22.1 and 26.0 months of age. This is supported by the approximately 24% higher lifetime milk production in relation to the latest calving cows (P<0.01). Late commencement of the first milking (especially after 28 months) causes a considerable decrease in the first lactation milk yield and lifetime milk production, shortens the productive period, reduces the number of calvings, and increases culling rate due to low milk yield and udder diseases.

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Connection between psychological holistic factor and life satisfaction in old age – propensity score methods

Abstract

Introduction. Holism has been poorly researched in the field of health and social gerontology. The old man is a whole, therefore he needs a holistic treatment. It means that we consider his bio-psycho-social and spiritual needs. The purpose of the research is to determine the relationship of a psychological holistic factor with life satisfaction in old age.

Material and methods. For the needs of the research work, a quantitative research method was used. A simple random sample was selected from the statistical set. The survey included 1064 elderly people in Slovenia (65 years and over) in ten statistical regions living in the domestic (n=532) and institutional (n=532). Environment. Sample realization was 61.6 % (656 correct questionnaires). According to demographic data, the survey involved 470 (71.6%) women and 186 (28.4%) men. The average age of the respondent was 78.2 years. The data was analyzed with the R MICE package. The analysis of causal effects and conditional associations advanced statistical methods, i.e. propensity score methods, and a questionnaire as a structured measurement instrument were used.

Results. Obtained research results imply a scientific contribution in the field of quality management of people in old age and their life quality. On the basis of statistical calculations, the hypothesis that the psychological holistic factor (R2=0.21) is related to life satisfaction in old age is confirmed. We proved that indexes: social networks (R2=0.176), positive emotions (R2=0.366), loneliness (R2=0.151), cognitive abilities (R2=0.162) studied within a psychological holistic factor affect life satisfaction.

Discussion and conclusion. Research confirmed that within the psychological factor, the most intimately related to life satisfaction is the emotional index, followed by the index of social networks, cognitive abilities and the last index of loneliness. For the holistic treatment of old man, in which the psychological factor is the only one of the four holistic factors, both structural and process changes are required for achievement of better outcomes, in our case, higher levels of satisfaction with life in old age.

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