11 resultados para Method of the ascension of the concrete and abstract

em Brock University, Canada


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It is common practice to initiate supplemental feeding in newborns if body weight decreases by 7-10% in the first few days after birth (7-10% rule). Standard hospital procedure is to initiate intravenous therapy once a woman is admitted to give birth. However, little is known about the relationship between intrapartum intravenous therapy and the amount of weight loss in the newborn. The present research was undertaken in order to determine what factors contribute to weight loss in a newborn, and to examine the relationship between the practice of intravenous intrapartum therapy and the extent of weight loss post-birth. Using a cross-sectional design with a systematic random sample of 100 mother-baby dyads, we examined properties of delivery that have the potential to impact weight loss in the newborn, including method of delivery, parity, duration of labour, volume of intravenous therapy, feeding method, and birth attendant. This study indicated that the volume of intravenous therapy and method of delivery are significant predictors of weight loss in the newborn (R2=15.5, p<0.01). ROC curve analysis identified an intravenous volume cut-point of 1225 ml that would elicit a high measure of sensitivity (91.3%), and demonstrated significant Kappa agreement (p<0.01) with excess newborn weight loss. It was concluded that infusion of intravenous therapy and natural birth delivery are discriminant factors that influence excess weight loss in newborn infants. Acknowledgement of these factors should be considered in clinical practice.

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Intracerebroventricular (ICV) administration of bombesin (BN) induces a syndrome characterized by stereotypic locomotion and grooming, hyperactivity and sleep elimination, hyperglycemia and hypothermia, hyperhemodynamics, feeding inhibition, and gastrointestinal function changes. Mammalian BN-like peptides (MBNs), e.g. gastrin-releasing peptide (GRP), Neuromedin C (NMC), and Neuromedin B (NMB), have been detected in the central nervous system. Radio-labeled BN binds to specific sites in discrete cerebral regions. Two specific BN receptor subtypes (GRP receptor and NMB receptor) have been identified in numerous brain regions. The quantitative 2-[14C]deoxyglucose ([14C]20G) autoradiographic method was used to map local cerebral glucose utilization (LCGU) in the rat brain following ICV injection of BN (vehicle, BN O.1Jlg, O.5Jlg). At each dose, experiments were conducted in freely moving or restrained conditions to determine whether alterations in cerebral function were the result of BN central administration, or were the result of BN-induced motor stereotypy. The anteroventral thalamic nucleus (AV) (p=O.029), especially its ventrolateral portion (AVVL) (pof metabolism under both restraint conditions. The effect was treatment dependent without interaction of the restraint conditions. Of all the regions that were reported to have high densities of BN receptors, the internal granular layer of the olfactory bulb (IGr) (p=O.028), and the suprachiasmatic nucleus (SCh) (p=O.003) exhibited BN treatment effects. BN effects on LCGU were also observed in the median eminence (ME) (p=O.011). Restraint, however, decreased LCGU in the lateral dorsal thalamic nucleus, ventrolateral and dorsomedial parts (LOVL and LOOM) (p=O.044, p=O.009), and the lateral geniculate (LG) (p=O.027). In sum, BN induced a marked and highly localized alteration in cerebral metabolism within parts of the anterior thalamus, which is the principle relay in the limbic circuitry. BN effects were also observed in IGr, Mi, SCh, and ME. Effects of restraint were found in LOVL, LOOM, and LG. It is suggested that increased LCGU in AV and AVVL may be the result of functional change in the limbic circuitry and the hypothalamus caused by BN receptor functional modification. In IGr, increased LCGU following BN administration is considered to be mainly the result the activation of NMB receptor, a subtype of BN receptors. In SCh, increased LCGU is believed to be caused both by BN effects on the thalamic, the hypothalamic, and the limbic functions and by activation of GRP receptor, another BN receptors subtype found in SCh. In ME, increased LCGU is suggested to be caused by BN effects on the hypothalamic functions, especially those related to the neuroendocrine functions. None of the alterations seen in these regions reflects the emission of stereotyped motor behaviors. Rather, they reflect a direct influence of BN central administration upon functioning of the cerebral regions influenced by BN administration. The restraint effects seen in LO, including LOOM and LOVL, are suggested to be the result of altered behavioral expression. The restraint effects seen in LG is suggested to be the result of reduced locomotion.

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Linear alkylbenzenes, LAB, formed by the Alel3 or HF catalyzed alkylation of benzene are common raw materials for surfactant manufacture. Normally they are sulphonated using S03 or oleum to give the corresponding linear alkylbenzene sulphonates In >95 % yield. As concern has grown about the environmental impact of surfactants,' questions have been raised about the trace levels of unreacted raw materials, linear alkylbenzenes and minor impurities present in them. With the advent of modem analytical instruments and techniques, namely GCIMS, the opportunity has arisen to identify the exact nature of these impurities and to determine the actual levels of them present in the commercial linear ,alkylbenzenes. The object of the proposed study was to separate, identify and quantify major and minor components (1-10%) in commercial linear alkylbenzenes. The focus of this study was on the structure elucidation and determination of impurities and on the qualitative determination of them in all analyzed linear alkylbenzene samples. A gas chromatography/mass spectrometry, (GCIMS) study was performed o~ five samples from the same manufacturer (different production dates) and then it was followed by the analyses of ten commercial linear alkylbenzenes from four different suppliers. All the major components, namely linear alkylbenzene isomers, followed the same elution pattern with the 2-phenyl isomer eluting last. The individual isomers were identified by interpretation of their electron impact and chemical ionization mass spectra. The percent isomer distribution was found to be different from sample to sample. Average molecular weights were calculated using two methods, GC and GCIMS, and compared with the results reported on the Certificate of Analyses (C.O.A.) provided by the manufacturers of commercial linear alkylbenzenes. The GC results in most cases agreed with the reported values, whereas GC/MS results were significantly lower, between 0.41 and 3.29 amu. The minor components, impurities such as branched alkylbenzenes and dialkyltetralins eluted according to their molecular weights. Their fragmentation patterns were studied using electron impact ionization mode and their molecular weight ions confirmed by a 'soft ionization technique', chemical ionization. The level of impurities present i~ the analyzed commercial linear alkylbenzenes was expressed as the percent of the total sample weight, as well as, in mg/g. The percent of impurities was observed to vary between 4.5 % and 16.8 % with the highest being in sample "I". Quantitation (mg/g) of impurities such as branched alkylbenzenes and dialkyltetralins was done using cis/trans-l,4,6,7-tetramethyltetralin as an internal standard. Samples were analyzed using .GC/MS system operating under full scan and single ion monitoring data acquisition modes. The latter data acquisition mode, which offers higher sensitivity, was used to analyze all samples under investigation for presence of linear dialkyltetralins. Dialkyltetralins were reported quantitatively, whereas branched alkylbenzenes were reported semi-qualitatively. The GC/MS method that was developed during the course of this study allowed identification of some other trace impurities present in commercial LABs. Compounds such as non-linear dialkyltetralins, dialkylindanes, diphenylalkanes and alkylnaphthalenes were identified but their detailed structure elucidation and the quantitation was beyond the scope of this study. However, further investigation of these compounds will be the subject of a future study.

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Factors affecting the detennination of PAHs by capillary GC/MS were studied. The effect of the initial column temperature and the injection solvent on the peak areas and heights of sixteen PAHs, considered as priority pollutants, USillg crosslinked methyl silicone (DB!) and 5% diphenyl, 94% dimethyl, 1% vinyl polysiloxane (DBS) columns was examined. The possibility of using high boiling point alcohols especially butanol, pentanol, cyclopentanol, and hexanol as injection solvents was investigated. Studies were carried out to optimize the initial column temperature for each of the alcohols. It was found that the optimum initial column temperature is dependent on the solvent employed. The peak areas and heights of the PAHs are enhanced when the initial column temperature is 10-20 c above the boiling point of the solvent using DB5 column, and the same or 10 C above the boiling point of the solvent using DB1 column. Comparing the peak signals of the PAHs using the alcohols, p-xylene, n-octane, and nonane as injection solvents, hexanol gave the greatest peak areas and heights of the PAHs particularly the late-eluted peaks. The detection limits were at low pg levels, ranging from 6.0 pg for fluorene t9 83.6 pg for benzo(a)pyrene. The effect of the initial column temperature on the peak shape and the separation efficiency of the PARs was also studied using DB1 and DB5 columns. Fronting or splitting of the peaks was obseIVed at very low initial column temperature. When high initial column temperature was used, tailing of the peaks appeared. Great difference between DB! and.DB5 columns in the range of the initial column temperature in which symmetrical.peaks of PAHs can be obtained is observed. Wider ranges were shown using DB5 column. Resolution of the closely-eluted PAHs was also affected by the initial column temperature depending on the stationary phase employed. In the case of DB5, only the earlyeluted PAHs were affected; whereas, with DB1, all PAHs were affected. An analytical procedure utilizing solid phase extraction with bonded phase silica (C8) cartridges combined with GC/MS was developed to analyze PAHs in water as an alternative method to those based on the extraction with organic solvent. This simple procedure involved passing a 50 ml of spiked water sample through C8 bonded phase silica cartridges at 10 ml/min, dried by passing a gentle flow of nitrogen at 20 ml/min for 30 sec, and eluting the trapped PAHs with 500 Jll of p-xylene at 0.3 ml/min. The recoveries of PAHs were greater than 80%, with less than 10% relative standard deviations of nine determinations. No major contaminants were present that could interfere with the recognition of PAHs. It was also found that these bonded phase silica cartridges can be re-used for the extraction of PAHs from water.

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The x-ray crystal structure of thiamine hydroiodide,C1ZH18N40S12' has been determined. The unit cell parameters are a = 13.84 ± 0.03, o b = 7.44 ± 0.01, c = 20.24 ± 0.02 A, 8 = 120.52 ± 0.07°, space group P2/c, z = 4. A total of 1445 reflections having ,2 > 2o(F2), 26 < 40° were collected on a Picker four-circle diffractometer with MoKa radiation by the 26 scan technique. The structure was solved by the heavy atom method. The iodine and sulphur atoms were refined anisotropically; only the positional parameters were refined for the hydrogen atoms. Successive least squares cycles yielded an unweighted R factor of 0.054. The site of protonation of the pyrimidine ring is the nitrogen opposite the amino group. The overall structure conforms very closely to the structures of other related thiamine compounds. The bonding surrounding the iodine atoms is distorted tetrahedral. The iodine atoms make several contacts with surrounding atoms most of them at or near the van der Waal's distances A thiaminium tetrachlorocobaltate salt was produced whose molecular and crystal structure was j~dged to be isomorphous to thiaminium tetrachlorocadmate.

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Part I - Fluorinated Compounds A method has been developed for the extraction, concentration, and determination of two unique fluorinated compounds from the sediments of Lake Ontario. These compounds originated from a common industrial landfill, and have been carried to Lake Ontario by the Niagara River. Sediment samples from the Mississauga basin of Lake Ontario have been evaluated for these compounds and a depositional trend was established. The sediments were extracted by accelerated solvent extraction (ASE) and then underwent clean-up, fractionation, solvent exchange, and were concentrated by reduction under nitrogen gas. The concentrated extracts were analyzed by gas chromatography - electron capture negative ionization - mass spectrometry. The depositional profile determined here is reflective of the operation of the landfill and shows that these compounds are still found at concentrations well above background levels. These increased levels have been attributed to physical disturbances of previously deposited contaminated sediments, and probable continued leaching from the dumpsite. Part II - Polycyclic Aromatic Hydrocarbons Gas chromatography/mass spectrometry is the most common method for the determination of polycyclic aromatic hydrocarbons (PAHs) from various matrices. Mass discrimination of high-boiling compounds in gas chromatographic methods is well known. The use of high-boiling injection solvents shows substantial increase in the response of late-eluting peaks. These solvents have an increased efficiently in the transfer of solutes from the injector to the analytical column. The effect of I-butanol, I-pentanol, cyclopentanol, I-hexanol, toluene and n-octane, as injection solvents, was studied. Higher-boiling solvents yield increased response for all PAHs. I -Hexanol is the best solvent, in terms of P AH response, but in this solvent P AHs were more susceptible to chromatographic problems such as peak splitting and tailing. Toluene was found to be the most forgiving solvent in terms of peak symmetry and response. It offered the smallest discrepancies in response, and symmetry over a wide range of initial column temperatures.

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The Clemente Course in the Humanities is an anti-poverty intervention for adults who self-identity as "poor" and humanities instructors. The course was created in 1995 by journalist Earl Shorris, who based the curriculum on a Socratic method of pedagogy and the "great books" canon of Robert Hutchins. It began as a community-based initiative in urban US settings, but since 1997 Mayan, Yup'ik and Cherokee iterations have been created, as well as on-campus bridge courses for non-traditional students to explore college-level education in Canada and the USA. The course potentially conflicts with critical pedagogy because the critical theories of Paulo Freire and contemporary cultural studies reject traditional notions of both the canon and teaching. However, a comparison between Shorris' and bell hooks' theories of oppression reveals significant similarities between his "surround of force" and her "capitalist imperialist white supremacist patriarchy," with implications for liberal studies and critical pedagogy.

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The purpose of the study was to investigate the effect of a 16 session stickhandling and puck control (SPC) off-ice training intervention on SPC skills and wrist shot performance variables. Eighteen female collegiate ice hockey players participated in a crossover design training intervention, whereby players were randomly assigned to two groups. Each group completed 16 SPC training sessions in two conditions [normal vision (NV) and restricted vision (RV)]. Measures obtained after the training intervention revealed significant improvements in SPC skills and wrist shot accuracy. Order of training condition did not reach significance, meaning that SPC improvement occurred as a result of total training volume as opposed to order of training condition. However, overall changes in the RV-NV condition revealed consistently higher effect sizes, meaning a greater improvement in performance. Therefore, support can be provided for this technical approach to SPC training and an alternative method of challenging SPC skills.

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This thesis explores Aboriginal women's access to and success within universities through an examination of Aboriginal women's educational narratives, along with input from key service providers from both the Aboriginal and non-Aboriginal community. Implemented through the Wildfire Research Method, participants engaged in a consensusbased vision of accessible education that honours the spiritual, emotional, intellectual, and physical elements necessary for the success of Aboriginal women in university. This study positions Aboriginal women as agents of social change by allowing them to define their own needs and offer viable solutions to those needs. Further, it connects service providers from the many disconnected sectors that implicate Aboriginal women's education access. The realities of Aboriginal women are contextualized through historical, sociocultural, and political analyses, revealing the need for a decolonizing educational approach. This fosters a shift away from a deficit model toward a cultural and linguistic assets based approach that emphasizes the need for strong cultural identity formation. Participants revealed academic, cultural, and linguistic barriers and offered clear educational specifications for responsive and culturally relevant programming that will assist Aboriginal women in developing and maintaining strong cultural identities. Findings reveal the need for curriculum that focuses on decolonizing and reclaiming Aboriginal women's identities, and program outcomes that encourage balance between two worldviews-traditional and academic-through the application of cultural traditions to modern contexts, along with programming that responds to the immediate needs of Aboriginal women such as childcare, housing, and funding, and provide an opportunity for universities and educators to engage in responsive and culturally grounded educational approaches.

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The opioid receptors consist of three main subtypes; μ, δ, and κ. Previous binding studies have shown that fragments of the milk protein, β-casein, known as β-casomorphins are agonists of these receptors which are selective for the μ receptor subtype. Using the crystal structures of these three receptors, computational molecular docking studies were done using the software GOLD to determine the conformation of β-casomorphin-5 and 7 when they bind to these three opioid receptors. GOLD was able to discriminate among the three receptors when docking the rigid ligands co-crystalized with the receptors. However, GOLD could not discriminate among the three receptors for either of the highly flexible β-casomorphins. A per amino acid scoring method was developed to overcome this problem. This method was used to predict the conformation of both β-casomorphin-5 and 7 in the μ receptor and determine that the two amino acid residues, Lys303 and Trp318 of the μ receptor are responsible for discriminating among the three receptor subtypes for binding of the β-casomorphin-5 and 7.