Comparison of sustainability of technologies for water desalination

The aim of this work is to perform an in-depth overview on the sustainability of several major commercialized technologies for water desalination and to identify the challenges and propose suggestions for the development of water desalination technologies. The overview of those technologies mainly focuses on the sustainability from the viewpoint of total capital investment, total product cost, energy consumption and global warming index. Additionally, a systematic sustainability assessment methodology has been introduced to validate the assessment process. Conclusions are:1) Reverse osmosis desalination (RO) plants are better than multi-stage flash distillation (MSF) desalination plants and multiple-effect distillation (MED) desalination plants from the viewpoint of energy consumption, global warming index and total production cost; 2)Though energy intensive, MSF plants and MED plants secure their advantages over RO plants by lower total capital investment, wider applicability and purer water desalted and they are still likely to flourish in energy-rich area;3) Water production stage and wastewater disposal stage are the two stages during which most pollutant gases are emitted. The water production stage alone contributes approximately 80~90% of the total pollutant gases emission during its life cycle; 4)The total capital cost per m3 desalted water decreases remarkably with the increasing of plant capacity. The differences between the capital cost per m3 desalted water of RO and other desalination plants will decrease as the capacity increases; 5) It is found that utilities costs serve as the major part of the total product cost, and they account for 91.16%, 85.55% and 71.26% of the total product cost for MSF, MED and RO plants, respectively; 6) The absolute superiority of given technology depends on the actual social-economic situation (energy prices, social policies, technology advancements).

Usability comparison of open source content management systems

The purpose of this thesis is to study, investigate and compare usability of open source cms. The thesis examines and compares usability aspect of some open source cms. The research is divided into two complementary parts –theoretical part and analytical part. The theoretical part mainly describes open source web content management systems, usability and the evaluation methods. The analytical part is to compare and analyze the results found from the empirical research. Heuristic evaluation method was used to measure usability problems in the interfaces. The study is fairly limited in scope; six tasks were designed and implemented in each interface for discovering defects in the interfaces. Usability problems were rated according to their level of severity. Time it took by each task, level of problem’s severity and type of heuristics violated will be recorded, analyzed and compared. The results of this study indicate that the comparing systems provide usable interfaces, and WordPress is recognized as the most usable system.

Analysis of the DF508 mutation in a Brazilian cystic fibrosis population: comparison of pulmonary status of homozygotes with other patients

Sixty-one cystic fibrosis patients admitted for check-up or antibiotic treatment were enrolled for genetic and clinical evaluation. Genetic analysis was performed on blood samples stored on neonatal screening cards using PCR techniques to determine the presence of DF508 mutations. Clinical evaluation included Shwachman and Chrispin-Norman scores, age at onset of symptoms and diagnosis, spirometry, awake and sleep pulse oximetry, hyponychial angle measurement and presence of chronic Pseudomonas aeruginosa colonization. Eighteen patients (29.5%) were homozygous for the DF508 mutation, 26 (42.6%) had one DF508 mutation and 17 (27.9%) were noncarriers, corresponding to a 50.8% prevalence of the mutation in the whole population. Analysis by the Kruskal-Wallis test for comparison of genetic status with continuous variables or by the chi-square test and logistic regression for dichotomous variables showed no significant differences between any two groups for a = 0.05. We conclude that genetic status in relation to the DF508 mutation is not associated with pulmonary status as evaluated by the above variables

Comparison of three methods for the determination of baroreflex sensitivity in conscious rats

Baroreflex sensitivity was studied in the same group of conscious rats using vasoactive drugs (phenylephrine and sodium nitroprusside) administered by three different approaches: 1) bolus injection, 2) steady-state (blood pressure (BP) changes produced in steps), 3) ramp infusion (30 s, brief infusion). The heart rate (HR) responses were evaluated by the mean index (mean ratio of all HR changes and mean arterial pressure (MAP) changes), by linear regression and by the logistic method (maximum gain of the sigmoid curve by a logistic function). The experiments were performed on three consecutive days. Basal MAP and resting HR were similar on all days of the study. Bradycardic responses evaluated by the mean index (-1.5 ± 0.2, -2.1 ± 0.2 and -1.6 ± 0.2 bpm/mmHg) and linear regression (-1.8 ± 0.3, -1.4 ± 0.3 and -1.7 ± 0.2 bpm/mmHg) were similar for all three approaches used to change blood pressure. The tachycardic responses to decreases of MAP were similar when evaluated by linear regression (-3.9 ± 0.8, -2.1 ± 0.7 and -3.8 ± 0.4 bpm/mmHg). However, the tachycardic mean index (-3.1 ± 0.4, -6.6 ± 1 and -3.6 ± 0.5 bpm/mmHg) was higher when assessed by the steady-state method. The average gain evaluated by logistic function (-3.5 ± 0.6, -7.6 ± 1.3 and -3.8 ± 0.4 bpm/mmHg) was similar to the reflex tachycardic values, but different from the bradycardic values. Since different ways to change BP may alter the afferent baroreceptor function, the MAP changes obtained during short periods of time (up to 30 s: bolus and ramp infusion) are more appropriate to prevent the acute resetting. Assessment of the baroreflex sensitivity by mean index and linear regression permits a separate analysis of gain for reflex bradycardia and reflex tachycardia. Although two values of baroreflex sensitivity cannot be evaluated by a single symmetric logistic function, this method has the advantage of better comparing the baroreflex sensitivity of animals with different basal blood pressures.

Reactivity of anti-thyroid antibodies to thyroglobulin tryptic fragments: comparison of autoimmune and non-autoimmune thyroid diseases

Studies concerning the antigenicity of thyroglobulin fragments allow the characterization of the epitopes but do not consider the role of heavier antigenic fragments that could result in vivo from the action of endoproteases. Here we assess the relative importance of the fragments obtained from thyroglobulin by limited proteolysis with trypsin and compare by immunoblotting their reactivity to serum from patients with autoimmune (Graves' disease and Hashimoto's thyroiditis) and non-autoimmune (subacute thyroiditis) disease. The results showed no difference in frequency of recognition of any peptide by sera from patients with autoimmune thyroiditis. In contrast, sera from patients with subacute thyroiditis reacted more frequently with a peptide of 80 kDa. These results suggest the presence of antibody subpopulations directed at fragments produced in vivo by enzymatic cleavage of thyroglobulin. This fragment and antibodies to it may represent markers for subacute thyroiditis.

Pharmacological and histopathological study of cyclophosphamide-induced hemorrhagic cystitis - comparison of the effects of dexamethasone and Mesna

Chemotherapy with oxazaphosphorines, such as cyclophosphamide (CYP), is often limited by unacceptable urotoxicity. Without uroprotection, hemorrhagic cystitis (HC) becomes dose-limiting. To compare the uroprotective efficacy of classical 2-mercaptoethanesulfonic acid (Mesna) treatment with dexamethasone in CYP-induced HC, male Wistar rats (150-200 g; N = 6 in each group) were treated with saline or Mesna (40 mg/kg, ip) immediately and 4 and 8 h after ip administration of CYP (200 mg/kg). One, 2 or 3 doses of Mesna were replaced with dexamethasone (1 mg/kg, ip). The animals were sacrificed 24 h later. Cystitis was evaluated by determining the changes in bladder wet weight (BWW) and by macroscopic and microscopic analysis. CYP treatment induced a marked increased in BWW (162%, P<0.05), which was significantly inhibited by treatment with 3 doses of Mesna (P<0.05; 80%). The replacement of 1 or 2 doses of Mesna with dexamethasone reduced the increase in BWW by 83.3 and 95%, respectively. Macroscopic analysis of the bladder of rats with CYP-induced HC showed severe edema and hemorrhage, confirmed by microscopic analysis, that also showed mucosal erosion, inflammatory cell infiltration and ulcerations. The replacement of 1 or 2 doses of Mesna with dexamethasone inhibited the CYP-induced increase in BWW and almost abolished the macroscopic and microscopic alterations, with no significant difference between the effects of Mesna and dexamethasone, indicating that both drugs were efficient in blocking HC. However, although the replacement of all Mesna doses with dexamethasone reduced the edema, it did not prevent HC, suggesting that Mesna is necessary for the initial uroprotection.

Testing Accrual-Based Model for Detecting Earnings Management: Comparison of Finland and France

The aim of this study is to test the accrual-based model suggested by Dechow et al. (1995) in order to detect and compare earnings management practices in Finnish and French companies. Also the impact of financial crisis of 2008 on earnings management behavior in these countries is tested by dividing the whole time period of 2003-2012 into two sub-periods: pre-crisis (2003-2008) and post-crisis (2009-2012). Results support the idea that companies in both countries have significant earnings management practices. During the post-crisis period companies in Finland show income inflating practices, while in France the opposite tendency is noticed (income deflating) during the same period. Results of the assumption that managers in highly concentrated companies are engaged in income enhancing practices vary in two countries. While in Finland managers are trying to show better performance for bonuses or other contractual compensation motivations, in France they avoid paying dividends or high taxes.

Connexin hemichannels and cell-cell channels: comparison of properties

Connexin46 (Cx46) forms functional hemichannels in the absence of contact by an apposed hemichannel and we have used these hemichannels to study gating and permeation at the single channel level with high time resolution. Using both cell-attached and -excised patch configurations, we find that single Cx46 hemichannels exhibit some properties expected of half of a gap junction channel, as well as novel properties. Cx46 hemichannels have a large unitary conductance (~300 pS) and a relatively large pore as inferred from permeability to TEA. Both monovalent cations and anions can permeate, but cations are substantially more permeable. The open channel conductance shows marked inward rectification in symmetric salts. We find that the conductance and permeability properties of Cx46 cell-cell channels can be explained by the series addition of two hemichannels. These data suggest that the pore structures of unapposed hemichannels and cell-cell channels are conserved. Also like cell-cell channels, unapposed Cx46 hemichannels are closed by elevated levels of H+ or Ca2+ ions on the cytoplasmic face. Closure occurs in excised patches indicating that the actions of these agents do not require a soluble cytoplasmic factor. Fast (<0.5 ms) application of H+ to either side of the open hemichannel causes an immediate small reduction in unitary conductance followed by complete closure with latencies that are dependent on H+ concentration and side of application; sensitivity is much greater to H+ on the cytoplasmic side. Closure by cytoplasmic H+ does not require that the hemichannel be open. Thus, H+ ions readily permeate Cx46 hemichannels, but at high enough concentration close them by acting at a cytoplasmic site(s) that causes a conformational change resulting in complete closure. Extracellular H+ may permeate to act on the cytoplasmic site or act on a lower affinity extracellular site. Thus, the unapposed hemichannel is a valuable tool in addressing fundamental questions concerning the operation of gap junction channels that are difficult to answer by existing methods. The ability of Cx46, and perhaps other connexins, to form functional unapposed hemichannels that are opened by moderate depolarization may represent an unexplored role of connexins as mediators of transport across the plasma membrane.

Comparison of AutoSetä and polysomnography for the detection of apnea-hypopnea events

The use of the flow vs time relationship obtained with the nasal prongs of the AutoSetä (AS) system (diagnosis mode) has been proposed to detect apneas and hypopneas in patients with reasonable nasal patency. Our aim was to compare the accuracy of AS to that of a computerized polysomnographic (PSG) system. The study was conducted on 56 individuals (45 men) with clinical characteristics of obstructive sleep apnea (OSA). Their mean (± SD) age was 44.6 ± 12 years and their body mass index was 31.3 ± 7 kg/m2. Data were submitted to parametric analysis to determine the agreement between methods and the intraclass correlation coefficient was calculated. The Student t-test and Bland and Altman plots were also used. Twelve patients had an apnea-hypopnea index (AHI) <10 in bed and 20 had values >40. The mean (± SD) AHI PSG index of 37.6 (28.8) was significantly lower (P = 0.0003) than AHI AS (41.8 (25.3)), but there was a high intraclass correlation coefficient (0.93), with 0.016 variance. For a threshold of AHI of 20, AS showed 73.0% accuracy, 97% sensitivity and 60% specificity, with positive and negative predictive values of 78% and 93%, respectively. Sensitivity, specificity and negative predictive values increased in parallel to the increase in AHI threshold for detecting OSA. However, when the differences of AHI PSG-AS were plotted against their means, the limits of agreement between the methods (95% of the differences) were +13 and -22, showing the discrepancy between the AHI values obtained with PSG and AS. Finally, cubic regression analysis was used to better predict the result of AHI PSG as a function of the method proposed, i.e., AHI AS. We conclude that, despite these differences, AHI measured by AutoSetä can be useful for the assessment of patients with high pre-test clinical probability of OSA, for whom standard PSG is not possible as an initial step in diagnosis.

Comparison of energy balances of steam explosion and torrefaction technologies

The present study introduce two pretreatment technologies which are torrefaction and steam explosion, and compare energy balance for both technologies to investigate and compare the use of these technologies to improve pelletization. In this research, torrefaction and steam explosion pretreatments were accomplished on the mixed small diameter wood (70%) with moisture content of 40 %, and logging residues (30%) with moisture content of 45 % at temperature 230 ̊C, and treatment duration 10 min. Competing methods were evaluated, and the results showed higher volumetric energy for steam explosion pellet than torrefied pellet.

Comparison of the quantification of caffeine in human plasma by gas chromatography and ELISA

In the present study we evaluated the precision of the ELISA method to quantify caffeine in human plasma and compared the results with those obtained by gas chromatography. A total of 58 samples were analyzed by gas chromatography using a nitrogen-phosphorus detector and routine techniques. For the ELISA test, the samples were diluted to obtain a concentration corresponding to 50% of the absorbance of the standard curve. To determine whether the proximity between the I50 of the standard curve and that of the sample would bring about a more precise result, the samples were divided into three blocks according to the criterion of difference, in modulus, of the I50 of the standard curve and of the I50 of the sample. The samples were classified into three groups. The first was composed of 20 samples with I50 up to 1.5 ng/ml, the second consisted of 21 samples with I50 ranging from 1.51 to 3 ng/ml, and the third of 17 samples with I50 ranging from 3.01 to 13 ng/ml. The determination coefficient (R² = 0.999) showed that the data obtained by gas chromatography represented a reliable basis. The results obtained by ELISA were also reliable, with an estimated Pearson correlation coefficient of 0.82 between the two methods. This coefficient for the different groups (0.88, 0.79 and 0.49 for groups 1, 2 and 3, respectively) showed greater reliability for the test with dilutions closer to I50.

Head-to-head comparison of dipyridamole, dobutamine and pacing stress echocardiography for the detection of myocardial ischemia in an animal model of coronary artery stenosis

To compare the sensitivity of dipyridamole, dobutamine and pacing stress echocardiography for the detection of myocardial ischemia we produced a physiologically significant stenosis in the left circumflex artery of 14 open-chest dogs (range: 50 to 89% reduction in luminal diameter). In each study, dobutamine (5 to 40 µg kg-1 min-1 in 3-min stages) and pacing (20 bpm increments, each 2 min, up to 260 bpm) were performed randomly, and then followed by dipyridamole (up to 0.84 mg/kg over 10 min). The positivity of stress echocardiography tests was quantitatively determined by a significant (P<0.05) reduction of or failure to increase absolute and percent systolic wall thickening in the stenotic artery supplied wall, as compared to the opposite wall (areas related to the left anterior descending artery). Systolic and diastolic frozen images were analyzed off-line by two blinded observers in the control and stress conditions. The results showed that 1) the sensitivity of dobutamine, dipyridamole and pacing stress tests was 57, 57 and 36%, respectively; 2) in animals with positive tests, the mean percent change of wall thickening in left ventricular ischemic segments was larger in the pacing (-19 ± 11%) and dipyridamole (-18 ± 16%) tests as compared to dobutamine (-9 ± 6%) (P = 0.05), but a similar mean reduction of wall thickening was observed when this variable was normalized to a control left ventricular segment (area related to the left anterior descending artery) (pacing: -16 ± 7%; dipyridamole: -25 ± 16%; dobutamine: -26 ± 10%; not significant), and 3) a significant correlation was observed between magnitude of coronary stenosis and left ventricular segmental dysfunction induced by ischemia in dogs submitted to positive stress tests. We conclude that the dobutamine and dipyridamole stress tests showed identical sensitivities for the detection of myocardial ischemia in this one-vessel disease animal model with a wide range of left circumflex artery stenosis. The pacing stress test was less sensitive, but the difference was not statistically significant. The magnitude of segmental left ventricular dysfunction induced by ischemia was similar in all stress tests evaluated.

Comparison of the quantitative competitive and semiquantitative RT-PCR methods for the determination of interferon-gamma mRNA levels in AIDS-free HIV-infected individuals

IFN-gamma mRNA expression was evaluated in nonstimulated peripheral blood mononuclear cells (PBMC) of HIV-infected and seronegative individuals using quantitative competitive and semiquantitative RT-PCR and the sensitivity of these methods was compared. A significant correlation was found between quantitative competitive and semiquantitative RT-PCR in samples of both HIV-seronegative (P = 0.004) and HIV-infected individuals (P = 0.0004). PBMC from HIV-infected individuals presented a remarkable increase of IFN-gamma mRNA expression, as determined by both types of RT-PCR methods. Semiquantitative RT-PCR even without an internal standard is also acceptable for measuring cytokine mRNA expression, but less reliable if small amounts are quantified. Moreover, we found that increased IFN-gammamRNA expression is independent of CD4+ cell count in AIDS-free HIV-infected patients.

Comparison of Pavlovian serial conditional discrimination in rats and hamsters in the same experimental situation

The present study compares behavioral changes between two distinct rodent groups, hamsters (Mesocricetus auratus) and Wistar rats, when submitted in the same homogeneous experimental situations to a serial conditional discrimination procedure which involves water deprivation and the processing of temporal variables. Both hamsters and rats acquired serial positive conditional discrimination as indicated by higher frequencies of magazine-oriented behavior during the tone followed by reinforcement (T+) and preceded by the feature stimulus light (L) and during the empty interval, than during the tone alone not followed by reinforcement (T-). Rats' frequencies of magazine-oriented behavior were high during T+ and T-, initially during training, and decreased during T- as the training progressed. However, the hamsters' frequencies of magazine-oriented behavior started very low and increased only during T+ as the training progressed. Comparison of the frequencies of magazine-oriented behavior during the empty interval in relation to the frequencies during the preceding L period showed that rats' frequencies remained very high and hamsters' frequencies increased during training. These results suggest that rats and hamsters have different behavioral strategies for the acquisition of a conditional discrimination. The results of the comparisons made in these experiments support the view of the importance of an ecological psychology approach to the understanding of complex learning in animals.

Comparison of methods for urinary albumin determination in patients with type 1 diabetes

We tested the correlation of the albumin-to-creatinine ratio (A/C) in an early-morning urine sample, measured with a commercial kit (DCA 2000®), with the conventional immunoturbidimetric determination in the laboratory and with overnight albumin excretion rate (reference method). Fifty-five type 1 diabetic adolescents had their first-morning urine collected on the 1st and 8th day of the period. Urinary albumin and creatinine were determined immediately using the DCA 2000® kit. Samples were also stored for laboratory analysis. To evaluate the correlation between early-morning urinary A/C ratio and overnight albumin excretion rate, 16 subjects had a timed overnight urine collection. A/C ratios determined with the DCA 2000® kit and by the laboratory method were 13.1 ± 20.5 and 20.4 ± 46.3 mg/g, respectively. A/C results by both methods proved to be strongly correlated (r = 0.98, P<0.001). DCA 2000®-determined A/C showed 50% sensitivity and 100% specificity when compared to the reference method. Spot urinary A/C of the subset of 16 subjects significantly correlated with their overnight albumin excretion rate (r = 0.98, P<0.001). Intraindividual variation ranged from 17 to 32% and from 9 to 63% for A/C and overnight albumin excretion rate, respectively. In conclusion, an early-morning specimen should be used instead of timed overnight urine and the A/C ratio is an accurate, reliable and easily determined parameter for the screening of diabetic nephropathy. Immediate measurement of the A/C ratio is feasible using the DCA 2000® kit. Intraindividual variability indicates the need for repeated determinations to confirm microalbuminuria and the diagnosis of incipient diabetic nephropathy.