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There is an increasing demand for herbal medicines in weight loss treatment. Some synthetic chemicals, such as sibutramine (SB), have been detected as adulterants in herbal formulations. In this study, two strategies using near infrared (NIR) spectroscopy have been developed to evaluate potential adulteration of herbal medicines with SB: a qualitative screening approach and a quantitative methodology based on multivariate calibration. Samples were composed by products commercialized as herbal medicines, as well as by laboratory adulterated samples. Spectra were obtained in the range of 14,000–4000 per cm. Using PLS‐DA, a correct classification of 100% was achieved for the external validation set. In the quantitative approach, the root mean squares error of prediction (RMSEP), for both PLS and MLR models, was 0.2%w/w. The results prove the potential of NIR spectroscopy and multivariate calibration in quantifying sibutramine in adulterated herbal medicines samples.  相似文献   
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In this paper, we analyse empirically how the legal framework affects the relationship between labour market conditions and dismissals. We use a pseudo-panel of Spanish data from 1987 to 2001. We find that Labour Law reforms have effects on the use of individual and collective dismissals although such effects are much lower than those related to the business cycle. The results also show a strategic use of the different types of dismissals, distorting the work of those institutions involved in dismissals.   相似文献   
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The allele frequencies for the 15 short tandem repeats included in the Power Plex-16 kit (Promega Corp., Madison, WI, USA) were determined in a sample of 429 unrelated individuals from five provinces of the Northern and Northeastern regions of Argentina. Three Northern provinces including Salta, Formosa and Chaco and two within the region surrounded by the Paraná and Uruguay Rivers commonly known as the Argentine Mesopotamia, including Misiones and Corrientes. Since in this region Entre Ríos Province is also present, previously published results were used for comparison. The calculated parameters: polymorphism information content (PIC); discrimination power (DP); matching probability (MP); typical paternity index (TPI) and power of exclusion (PE) showed Penta E to be the most valuable marker from the studied sample set. All loci met Hardy–Weinberg expectations using the Bonferroni correction for the number of loci analyzed, except D3S1358 in Salta and THO1 in Formosa provinces. Population differentiation test revealed that the Salta population sample data denoted significant differences for various loci when compared with the other province information presented here in, as well as with other published data sets.  相似文献   
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The article estimates the impact of Familias en Acción, a human development conditional cash transfer programme, on adult labour market outcomes in urban areas in Colombia. Relying on a regression discontinuity design and a large panel dataset, the article finds significant, largely positive, but heterogeneous programme effects on labour market outcomes. The findings suggest that antipoverty transfers enable a re-allocation of household productive resources among participant households.  相似文献   
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A rapid and highly species-specific real-time polymerase chain reaction (PCR) assay has been developed for the detection of capercaillie DNA (Tetrao urogallus) in meat and meat mixtures. The method combines the use of capercaillie-specific primers, that amplify a 142bp fragment of the mitochondrial 12S rRNA gene, and a positive control primer pair that amplifies a 141bp fragment of the nuclear 18S rRNA gene from eukaryotic DNA. SYBR(?) Green dye or TaqMan(?) fluorogenic probes were used to monitor the amplification of the target genes. Results obtained with the use of TaqMan(?) probes as detection platform increased the specificity of the real-time PCR assay in comparison with the results obtained using SYBR(?) Green. The proposed real-time PCR assay represents a rapid and straightforward method for the accurate identification of capercaillie that could be used by law enforcement agencies as a tool for the control of poaching and illegal trade of meat from this protected species.  相似文献   
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