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Journal articles on the topic "]+[628.4"
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Dragojevic, Svetlana, Mladenko Vasiljevic, Ana Mitrovic, Radica Dunjic, Srdjan Dikic, and Fadil Canovic. "Hyperprolactinaemia as a potential cause of infertility." Jugoslovenska medicinska biohemija 22, no. 4 (2003): 335–39. http://dx.doi.org/10.2298/jmh0304335d.
Full textAbstract:
Establishing of hormonal disturbances is one of the most important steps in infertility studies. The aim of the study was to evaluate the importance frequency and treatment efficiency of hyperprolactinaemia in infertile patients. Eighty-seven infertile patients have been examined in this study. Matched samples of periph?eral blood were taken for hormonal analyses in the early follicular, periovulatory and midluteal phases of the cycle. Between the 4th and 7th day of the cycle ultrasonographic and haemodynamic examinations have been carried out at the ovarian and uterine levels. Hyperprolactinaemia was detected in 25 women, in which prolactin levels ranged 628.4-8000 mIU/L. We started dopamine agonists (bromocriptine/cabergoline) treatment individually dosaged. Menstrual cycle as well as prolactin levels restored in all patients 3 months after treatment initiation. Hyperprolactinaemia can derange fertility potential so its early and precise detection and adequate therapy are essential for restoration of regular menstrual cycle and successful infertility treatment.
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McCoy, Andrew P., Dong Zhao, Teni Ladipo, Philip Agee, and Yunjeong Mo. "COMPARISON OF GREEN HOME ENERGY PERFORMANCE BETWEEN SIMULATION AND OBSERVATION: A CASE OF VIRGINIA, UNITED STATES." Journal of Green Building 13, no. 3 (June 2018): 70–88. http://dx.doi.org/10.3992/1943-4618.13.3.70.
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The United States has a long-term goal to reduce 50% of energy usage in buildings based on 2010 consumption levels. Home energy efficiency is often measured by laboratory experiments and computational simulation. Thus, there is little to no quantifiable evidence showing the extent of energy efficiency homes can achieve within the larger context of green building standards. The objective of this research is to identify actual home energy performance as an effect of green building technologies by comparing energy use from real-world observations and energy modeling. Results indicate a significant reduction of energy consumption at 43.7% per unit or 43.4% per square foot (i.e., 0.093 m2) and substantial financial savings at $628.4 per unit or $0.80 per square foot (i.e., $8.6 per m2) annually. Savings account for 2% of median annual household income or 46% of energy cost expenditures for an American home. Results also identify the construction type as a significant factor, yet building technology is not the only factor influencing a home's energy efficiency. The findings contribute to the body of knowledge in three aspects: (1) simulated energy usage is higher than actual energy usage; (2) energy modeling via simulation tools is particularly accurate for new construction; and (3) energy modeling, especially for existing buildings, is not accurate due to largely varying occupant behaviors.
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Shoba, H., N. Rajeshwari, and G. Nagaraja. "A Study on Physico-Mechanical Properties of Onion Varieties Under Koppal District, (Karnataka)." Current Agriculture Research Journal 5, no. 3 (November 24, 2017): 381–86. http://dx.doi.org/10.12944/carj.5.3.18.
Full textAbstract:
The physico-mechanical properties of four popular cultivable onion varieties i.e., Ballari red, Arka kalyan, Satara (local verity), Kalasa (local variety) in Koppal (Karnataka)were studied to form an important database for designing of storage structures, cleaning, grading, sorting and harvesting equipments. The equatorial diameter of all size category Ballari red onion variety ranged from 4.01 to 8.35 cm, polar diameter ranged from3.82 to 6.62 cm and thickness of Ballari red onion variety ranged from 1.25 to 2.51 cm where as the lowest values of equatorial diameter was observed in Kalasa (local variety) i.e., 3.2 to 7.12 cm, polar diameter ranged from 2.89 to 5.12 cm and thickness from 1.22 to 2.01 cm, respectively. Shape index of three out of four was oval in shape. The geometric mean diameter (Dgm) and arthematic mean diameter (Dam) of large, medium and small size verities as Ballari red, Arka kalyan, Satara, Kalasa had 2.65 to 5.09, 2.5 to 4.58, 2.35 to 4.43 and 2.23 to 4.13 cm, respectively. The highest mean value of bulk density from 678.9 to 390.42 kg/cm3was observed in Ballari red onion followed by Arka kalyan of 662.7to 390.42 kg/cm3, Satara 628.4 to 390.23 kg/cm3, Kalasa 618.59 to 385.24 kg/cm3and highest mean value of angle of repose which was observed in Ballari red i.e, 37o (large size) and lowest was observed 20.90o in Kalasa (small size) variety.
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Santana, Milana D. R., Brian Kliszczewicz, Franciele M. Vanderlei, Larissa R. L. Monteiro, Eli Carlos Martiniano, Yasmim M. de Moraes, Luana B. Mangueira, et al. "Autonomic responses induced by aerobic submaximal exercise in obese and overweight adolescents." Cardiology in the Young 29, no. 2 (February 2019): 169–73. http://dx.doi.org/10.1017/s1047951118002007.
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AbstractBackgroundGraded exercises tests are performed in adult populations; nonetheless, the use of this type of assessment is greatly understudied in overweight and obese adolescents.ObjectiveTo investigate heart rate autonomic responses to submaximal aerobic exercise in obese and overweight adolescents.MethodsWe recruited 40 adolescents divided into two groups: (1) overweight group comprising 10 boys and 10 girls between Z-score +1 and +2 and (2) obese group comprising 10 boys and 10 girls above Z-score >+2. Heart rate variability was analysed before (T1) and after exercise (T2–T4) on treadmill at a slope of 0%, with 70% of the maximal estimated heart rate (220 – age) for 20 minutes.ResultsHeart rate in the overweight group was: 93.2±10.52 bpm versus 120.8±13.49 bpm versus 94.6±11.65 bpm versus 93.0±9.23 bpm, and in the obese group was: 92.0±15.41 bpm versus 117.6±16.31 bpm versus 92.1±12.9 bpm versus 91.8±14.33 bpm. High frequency in the overweight group was: 640±633.1 ms2 versus 84±174.66 ms2 versus 603.5±655.31 ms2 versus 762.6±807.21 ms2, and in the obese group was: 628.4±779.81 ms2 versus 65.4±119.34 ms2 versus 506.2±482.70 ms2 versus 677.9±939.05 ms2; and root mean square of successive differences in the overweight group was: 37.9±18.81 ms versus 10.9±8.41 ms versus 32.8±24.07 ms versus 36.7±21.86 ms, and in the obese group was: 38.7±23.17 ms versus 11.5±8.62 ms versus 32.3±16.74 ms versus 37.3±24.21 ms. These values significantly changed during exercise compared with resting values in overweight and obese groups. Moreover, we also reported no significant difference of resting parasympathetic control of heart rate between obese and overweight adolescents.ConclusionThere was no significant difference of autonomic responses elicited by submaximal aerobic exercise between overweight and obese adolescents.
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Legnani, Cristina, Benilde Cosmi, Giuliana Guazzaloca, Claudia Pancani, Sergio Coccheri, and Gualtiero Palareti. "Risk of Venous Thromboembolism Recurrence: High Negative Predictive Value of D-dimer Performed after Oral Anticoagulation Is Stopped." Thrombosis and Haemostasis 87, no. 01 (2002): 7–12. http://dx.doi.org/10.1055/s-0037-1612936.
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SummaryIn some patients with previous venous thromboembolism (VTE) D-dimer levels (D-Dimer) tend to increase after oral anticoagulant therapy (OAT) is stopped. The aim of our study was to evaluate the predictive value of D-Dimer for the risk of VTE recurrence after OAT withdrawal. After a first episode of deep vein thrombosis (DVT) of the lower limbs and/or pulmonary embolism (PE), 396 patients (median age 67 years, 198 males) were followed from the day of OAT discontinuation for 21 months. D-dimer was measured on the day of OAT withdrawal (T1), 3-4 weeks (T2) and 3 months (+/− 10 days, T3) thereafter. The main outcome events of the study were: objectively documented recurrent DVT and/or PE. D-dimer was found to be increased in 15.5%, 40.3% and 46.2% of the patients at T1, T2 and T3, respectively. In 199 (50.2%) patients, D-dimer levels were elevated in at least one measurement. During a follow-up of 628.4 years, 40 recurrences were recorded (10.1% of patients; 6.4% patient-years of follow-up). D-dimer was increased in at least one measurement in 28 of these cases, but remained normal in 11 subjects (three of whom had recurrent events triggered by circumstantial factors, three with malignancyassociated factors) (in one subject D-dimer was not measured). The negative predictive value (NPV) of D-dimer was 95.6% (95% CI 91.6-98.1) at T3 and was even higher (96.7%; 95% CI 92.9-98.8) after exclusion of the six recurrences due to circumstantial factors. Only five idiopathic recurrences occurred in the 186 patients with consistently normal D-dimer. In conclusion, D-dimer has a high NPV for VTE recurrence when performed after OAT discontinuation.
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AMUDHA, B., Y. E. A. RAJ, and S. B. THAMPI. "A statistical analysis of the differences between rainfall estimated by Chennai DWR and conventional rainfall data on monthly and seasonal scales during the Indian northeast monsoon season." MAUSAM 68, no. 2 (November 30, 2021): 261–78. http://dx.doi.org/10.54302/mausam.v68i2.629.
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The first Doppler Weather Radar (DWR) of India Meteorological Department has been functional at Chennai since the year 2002 providing various meteorological and hydrological products. Validation and statistical analysis of the DWR estimated rainfall (RERF, x) data with rain gauge measured rainfall (RGRF, y) of 34 land based stations located in the semi-circular land area within 100 km radius of Chennai DWR (CDLR100) has been performed for the northeast monsoon (NEM) season of October-November-December (OND) for the 12 year period 2002-13. The monthly and seasonal data have been derived using more than 1.42 lakh discrete daily RERF values available at a high resolution of 333 m × 333 m. The major objective of the study is to compute the various statistical parameters of x and y including the bias between them on monthly and seasonal scales and to draw certain inferences. The analysis was done using three different types of averaging. The yearly means of x and y for OND over CDLR100 manifested both positive and negative epochs with the mean absolute deviation (MAD) computed as 11 cm (17% of mean). The short term normals over CDLR100 are derived as 274.9, 262.6, 96.5 and 629.8 mm for x and 243.8, 254.6, 128.0 and 627.4 mm for y for October, November, December and OND yielding bias values of -31.2, -8.0, 31.5 and -2.4 mm respectively. The MAD for OND rainfall computed by pooling in all the 12 ´ 34 values is quite substantial at around 19 cm (30% of mean). The RF bias for each month / NEM season is shown to be independent of the geographical locations of the stations using correlation analysis. Based on the raw values of x and a proportional correction technique, estimated values of at the 1.42 lakh grid points of CDLR100 were derived yielding spatial means of 273.3, 262.2, 92.5 and 628.4 mm for x and 243.4, 254.3, 122.9 and 622.1 mm for for the three months and OND respectively. The importance of size of the bias in the correct interpretation of x has been discussed. A few suggestions based on certain statistical considerations have been putforth for decreasing the bias.
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Pakakasama, Samart, Somtawin Sirireung, Bandit Thinkhamrop, Nongnuch Sirachainan, and Suradej Hongeng. "Efficacy of Deferasirox on Iron Chelation in Thalassemia Patients After Hematopoietic Stem Cell Transplantation." Blood 118, no. 21 (November 18, 2011): 3136. http://dx.doi.org/10.1182/blood.v118.21.3136.3136.
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Abstract Abstract 3136 Background Severe b thalassemia disease can be cured by hematopoietic stem cell transplantation (HSCT). Iron overload is one of the complications after HSCT in these patients. To prevent further tissue damages from excessive iron in the body, iron chelation is recommended in ex-thalassemics. Phlebotomy is an effective procedure removing iron excess in post HSCT thalassemia patients. However, the limitations of phlebotomy exist including young children, difficult access to peripheral veins, mixed chimerism, and non-compliance. Deferasirox has been shown to be an effectively oral iron chelator in transfusion-dependent thalassemia patients. The efficacy of deferasirox on iron removal in post HSCT survivors is limited. Objective To compare the efficacy of iron chelation between deferasirox and phlebotomy in post HSCT thalassemia patients Methods We included patients with severe b thalassemia who had received related or unrelated donor HSCT at least one year. The patients had no evidence of chronic GVHD or taking immunosuppressive agent at least 6 months. Twenty four patients were randomized into deferasirox or phlebotomy arm (12 patients each). The patients in deferasirox arm received deferasirox starting at the dose of 20 mg/kg/day. Adverse drug reactions were recorded. The dose of deferasirox was adjusted if severe side effects were recognized. The patients in phlebotomy arm underwent monthly 10 mL/kg blood withdrawal with normal saline replacement. Symptoms of hypotension and blood pressure were monitored during the procedure. Laboratory investigations including CBC, LFT, BUN, creatinine, and urinalysis were determined every month. Serum iron, total iron binding capacity and ferritin were measured every 3 months. Results The median age, M :F, types of thalassemia, and severity class were not different between two groups. In deferasirox group, the median dose of deferasirox was 18.9 mg/kg/day (range, 10 – 21.6 mg/kg). Two patients had reduced deferasirox dosage due to rising creatinine and GI symptoms. The baseline median (range) of alanine transaminase (ALT), transferrin saturation (TS), and ferritin were 68 U/L (14 – 332 U/L), 87.9% (35.6 – 106.1%), and 2, 802.9 (1, 332 – 6, 628.4 mg/dL) in deferasirox group and 53.5 U/L (32 – 78 U/L), 70.9 % (36.5 – 96.6%), and 1, 740 (1, 246.4 – 5, 780 mg/dL) in phlebotomy group. The 12-month median (range) of ALT, TS, and ferritin were 37.5 (12 – 508 U/L), 39.5% (28.3 – 70.6%), and 1, 743.5 mg/dL (721.1 – 3555.9 mg/dL) in deferasirox group and 40.5 U/L (27 – 97), 39.2% (22.2 – 95.2%), and 896.2 mg/dL (345.1 – 3, 740 mg/dL) in phlebotomy group. The median changes of ALT, TS, and ferritin at 12-month from baseline of these two groups were not different (Table 1). Conclusion Deferasirox was well tolerated and had manageable side effects in ex-thalassemics. Deferasirox reduced serum ferritin as effectively as phlebotomy in thalassemia patients after HSCT. Disclosures: No relevant conflicts of interest to declare.
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Vuong, Lan N., Toan D. Pham, Khanh T. Q. Le, Trung T. Ly, Ho L. Le, Diem T. N. Nguyen, Vu N. A. Ho, et al. "Micronized progesterone plus dydrogesterone versus micronized progesterone alone for luteal phase support in frozen-thawed cycles (MIDRONE): a prospective cohort study." Human Reproduction 36, no. 7 (April 30, 2021): 1821–31. http://dx.doi.org/10.1093/humrep/deab093.
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Abstract STUDY QUESTION Does the addition of oral dydrogesterone to vaginal progesterone as luteal phase support improve pregnancy outcomes during frozen embryo transfer (FET) cycles compared with vaginal progesterone alone? SUMMARY ANSWER Luteal phase support with oral dydrogesterone added to vaginal progesterone had a higher live birth rate and lower miscarriage rate compared with vaginal progesterone alone. WHAT IS KNOWN ALREADY Progesterone is an important hormone that triggers secretory transformation of the endometrium to allow implantation of the embryo. During IVF, exogenous progesterone is administered for luteal phase support. However, there is wide inter-individual variation in absorption of progesterone via the vaginal wall. Oral dydrogesterone is effective and well tolerated when used to provide luteal phase support after fresh embryo transfer. However, there are currently no data on the effectiveness of luteal phase support with the combination of dydrogesterone with vaginal micronized progesterone compared with vaginal micronized progesterone after FET. STUDY DESIGN, SIZE, DURATION Prospective cohort study conducted at an academic infertility center in Vietnam from 26 June 2019 to 30 March 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS We studied 1364 women undergoing IVF with FET. Luteal support was started when endometrial thickness reached ≥8 mm. The luteal support regimen was either vaginal micronized progesterone 400 mg twice daily plus oral dydrogesterone 10 mg twice daily (second part of the study) or vaginal micronized progesterone 400 mg twice daily (first 4 months of the study). In women with a positive pregnancy test, the appropriate luteal phase support regimen was continued until 7 weeks’ gestation. The primary endpoint was live birth after the first FET of the started cycle, with miscarriage <12 weeks as one of the secondary endpoints. MAIN RESULTS AND THE ROLE OF CHANCE The vaginal progesterone + dydrogesterone group and vaginal progesterone groups included 732 and 632 participants, respectively. Live birth rates were 46.3% versus 41.3%, respectively (rate ratio [RR] 1.12, 95% CI 0.99–1.27, P = 0.06; multivariate analysis RR 1.30 (95% CI 1.01–1.68), P = 0.042), with a statistically significant lower rate of miscarriage at <12 weeks in the progesterone + dydrogesterone versus progesterone group (3.4% versus 6.6%; RR 0.51, 95% CI 0.32–0.83; P = 0.009). Birth weight of both singletons (2971.0 ± 628.4 versus 3118.8 ± 559.2 g; P = 0.004) and twins (2175.5 ± 494.8 versus 2494.2 ± 584.7; P = 0.002) was significantly lower in the progesterone plus dydrogesterone versus progesterone group. LIMITATIONS, REASONS FOR CAUTION The main limitations of the study were the open-label design and the non-randomized nature of the sequential administration of study treatments. However, our systematic comparison of the two strategies was able to be performed much more rapidly than a conventional randomized controlled trial. In addition, the single ethnicity population limits external generalizability. WIDER IMPLICATIONS OF THE FINDINGS Our findings study suggest a role for oral dydrogesterone in addition to vaginal progesterone as luteal phase support in FET cycles to reduce the miscarriage rate and improve the live birth rate. Carefully planned prospective cohort studies with limited bias could be used as an alternative to randomized controlled clinical trials to inform clinical practice. STUDY FUNDING/COMPETING INTERESTS This study received no external funding. LNV has received speaker and conference fees from Merck, grant, speaker and conference fees from Merck Sharpe and Dohme, and speaker, conference and scientific board fees from Ferring; TMH has received speaker fees from Merck, Merck Sharp and Dohme, and Ferring; R.J.N. has received scientific board fees from Ferring and receives grant funding from the National Health and Medical Research Council (NHMRC) of Australia; BWM has acted as a paid consultant to Merck, ObsEva and Guerbet, and is the recipient of grant money from an NHMRC Investigator Grant. TRIAL REGISTRATION NUMBER NCT0399876.
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Sengupta, Amitava, and Jose Cancelas. "Leukemic Stem Cells and Progenitors Demonstrate Impaired Interaction with the Hematopoietic Microenvironment in Vivo in An Inducible Murine Model of Chronic Myelogenous Leukemia." Blood 112, no. 11 (November 16, 2008): 191. http://dx.doi.org/10.1182/blood.v112.11.191.191.
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Abstract Chronic myelogenous leukemia (CML) is a stem cell malignancy induced by p210 BCR-ABL and characterized by myeloproliferation in BM and egression of leukemic stem cells and progenitors (LSC/P) to extramedullary sites. Persistence of BCR-ABL+ HSC in patients under Imatinib suggests inhibition of ABL-kinase alone is not sufficient to eliminate the LSC/P. One of the major hallmarks of CML induced by signaling downstream BCR-ABL is the loss of control of the hematopoietic microenvironment on LSC/P. Expression of p210 BCR-ABL has been associated with loss of adhesion to the bone marrow, impaired migration in response to CXCL12 and decreased retention in the BM. In order to study the putative LSC/P niches in steady-state chronic-phase leukemia, we have analyzed the ability of LSC/P to proliferate and get retained in the bone marrow (BM) in an inducible model of CML. Binary transgenic SCL-tTA/TRE-BCR-ABL mice (Koschmieder S et al., Blood 2005) express p210 BCR-ABL in LSC/P upon doxycycline withdrawal (CML mice). Induced myeloproliferation was associated with activation of the downstream signaling effectors CrkL and p38-MAPK and expansion of circulating (Table 1) and splenic LSC/P but not in BM, suggesting massive LSC/P egression from the marrow (Table 2). Proliferation analysis showed that myeloid expansion in the spleen was secondary to increased cycling of Lin−Sca1+c-Kit+ (LSK) cells (3.1-fold increase in S-phase cells, P<0.05), but not in Lin−/c-Kit+ (LK) population, compared with the control spleens. In agreement with the LSC/P BM content data, the frequency of BM-derived LSK and LK cells incorporating BrdU in CML and in control mice remained similar, suggesting a specific egression of LSC/P from the BM to extramedullary sites. To test whether this model truly represented a model of BM LSC/P egression, we compared the splenic and BM LSC/P compared with their controls regarding their adhesion molecule expression, interaction with the hematopoietic microenvironment (HM) and homing to the overall marrow cavity and endosteal space. Splenic, but not BM-derived, LSK and LSK CD34+ ST-HSCs had increased cell surface expression of CD44 compared to controls (1.35 fold, P=0.006 and 1.23 fold, P<0.05 respectively) and decreased expression of L-selectin (8.7 fold, P<0.05) while expression of CXCR4, α4β1 and α5β1 integrins remain similar in bone marrow and splenocytes from CML and control mice. CML BM progenitors also showed 18-fold reduced adhesion to fibronectin and 1.4-fold increased migration towards CXCL12 compared to control BM progenitors. Myeloproliferative disease was transplantable into non-transgenic littermates and homing of CML BM progenitors was increased (4.3 fold, P<0.005) in myeloablated littermate recipient BM. However, lineage-negative leukemic BM-derived cells which had increased homing in BM of recipient mice had an impaired ability to migrate to the BM endosteal space compared with their littermate controls (control: 31 ± 18% vs CML mice: 17.6 ± 17%), suggesting an specific impairment to lodge in specialized anatomically-defined hematopoietic “niches”. Altogether, this murine model may represent an adequate in vivo system to analyze the ability of p210 BCR-ABL-expressing LSC/P to interact with BM niches and study the control of the hematopoietic microenvironment on LSC/P survival, proliferation and retention. Table 1 Increase in circulating LSC/P in the CML mice after withdrawal of doxycyclin Peripheral Blood LSK (×103)Cells/mL Blood P<0.05 LT-HSC(×103)Cells/mL Blood P<0.05 CFU-GM+BFU-E/mL Blood P<0.05 Control 1.56 ± 0.25 0.459 ± 0.29 60.86 ± 51.09 CML mice 3.56 ± 1.52 2.159 ± 2.03 869.6 ± 628.4 Table 2. Immunophenotypic analysis of BM and splenocytes in control and CML mice Population BM (Cells ×104) (Control) BM (Cells x104) (CML) SP (Cells ×104) (Control) SP (Cells x104) (CML) C-Kit + Sca1 + 24.3 ± 9.9 21.3 ± 11 6.8 ± 4.5 30.1 ± 12.3 (P<0.05) Mac1 + Gr1 + 1779 ± 307 1583 ± 265 78.4 ± 32 608 ± 377 (P<0.05) CFU-C/10 5 Cells 342 ± 66 334 ± 99 63.3 ± 7.09 79 ± 6.54 (P<0.05)
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Gaudreault, Nathalie, Nikit Kumar, Jessica Possada, and Robert Raffai. "Apolipoprotein E Suppresses Atherosclerosis by Reducing Leukocyte Recruitment to Atheroma." FASEB Journal 24, S1 (April 2010). http://dx.doi.org/10.1096/fasebj.24.1_supplement.628.4.
Full textDissertations / Theses on the topic "]+[628.4"
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Winfield, Jonathan. "Scale-up of microbial fuel cells for wastewater treatment." Thesis, University of the West of England, Bristol, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.572852.
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For decades microbial fuel cells (MFCs) have offered the potential to treat wastewater while concomitantly producing power, but to date scale-up has not been achieved. The goal for this thesis was initially to explore the capabilities of MFCs in the laboratory and then to test the technology in the wastewater treatment environment. The aim was to operate the demonstrator in an existing process, without altering infrastructure or adding extra energy (Le. pumping). Laboratory work yielded novel findings helping to achieve the thesis objective while also contributing to MFC knowledge. Investigations into the anodic development period revealed that inoculating while in continuous-flow primed MFCs for operation in conditions of high flow-rate. The phenomenon 'power overshoot' was described and its occurrence explained in terms of the internal resistance of the MFC. A new miniature tubular MFC was designed and up to seven units were connected in fluidic series (cascade) to mimic the trickling filter process. These efficiently removed up to 90% COD, to levels that comply with European guidelines. The influence that fluidic connection had on MFCs in terms of flow-rate and external resistance was described for the first time. To mimic hostile flocculating conditions, MFCs were fed feedstock with varying ferric chloride concentrations. Power production, COD treatment, metal reduction and increased pH were all achieved suggesting the technology could supplement and improve existing processes. Utilising experience gained in the laboratory and following visits to Wessex Water, the trickling filter was selected as test location for the demonstrator. Using a variation on the novel tubular design, under field conditions at the Saltford treatment plant, MFCs demonstrated the ability to produce power while reducing COD to levels acceptable for release into the environment. These results strongly support the hypothesis that MFCs are becoming ready to be incorporated into the wastewater treatment process.
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Brown, N. W. "Adsorption of organics in wastewater on nyex and electrochemical regeneration : development of a process." Thesis, University of Manchester, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556317.
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The removal of low concentrations of aqueous phase organics using adsorptive techniques has traditionally used high capacity adsorbent materials, for example activated carbons. The drawback of these materials is that regeneration can be costly and complex. An alternative approach reported in this thesis involves the use of a highly conductive material, a graphite intercalation compound (GIC), as an adsorbent. This material, which has been shown to be non-porous with a low surface area, is capable of electrochemical regeneration. This electrochemical regeneration is achieved by the oxidation of the organics in the anodic compartment of a simple, divided cell. In comparison with activated carbons, it has been demonstrated that adsorption is quick, with up to 88% of equilibrium loading being achieved within 2 minutes. 100% electrochemical regeneration can be achieved in a simple divided electrochemical cell with 10 minutes treatment, by passing a charge of 25 C g-1. The efficiency of electrochemical regeneration depends on a range of variables including charge passed, current density, treatment time, electrolyte concentration and composition and the adsorbent bed thickness. Multiple adsorption and regeneration cycles indicate that there is little loss of adsorptive capacity on regeneration. Whilst a number of modes of operation are potentially possible, the m4jority of the work reported in this thesis is based on separate adsorption and electrochemical regeneration. However, some work on a process involving continuous adsorption coupled with continuous and simultaneous electrochemical regeneration is presented. A third design involving continuous adsorption and regeneration within separate zones IN a single unit is given as an area for further research.
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Tang, S. L. "An optimization model - preliminary selection of appropriate technology in wastewater treatment alternatives." Thesis, Loughborough University, 1989. https://dspace.lboro.ac.uk/2134/10484.
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This research is concerned with the use of techniques of system analysis/operations research in the selection of the optimal - or most appropriate - wastewater treatment techniques in any given situation. An extensive investigation of existing treatment system optimization models, applying techniques of linear programming, dynamic programming and non-linear mathematical programming, has been carried out. None of these existing models deals with the socio-cultural and environmental conditions but merely with the economy of treatment. In this work the more subjective or intangible factors are included in the proposed optimization model in which twenty parameters are identified. These parameters are considered to be most important in the selection of appropriate alternatives for treating municipal wastewater. They include technical, economic, environmental and socio-cultural factors. The model was developed to rank a definite number (n) of wastewater treatment alternatives (decision variables) by the evaluation of the twenty parameters [ ... continues].
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Hewings, Guy. "Design and management of composting systems." Thesis, Cardiff University, 2007. http://orca.cf.ac.uk/55167/.
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Composting is an effective method of removing a large proportion of biodegradable waste from landfill. The CO2 produced by microbial activity demonstrates the rate of decomposition, and was measured in green waste composting in windrows, a forced aerated bay, an aerated test rig and related to the volatile solid content. The peak respiration rates were 35gC02kgVS",day"1 in windrows, and 290gCO2kgVS"1day"1 in the test rig. Knowing the rate of microbial activity, allows the volume of air required to supply sufficient oxygen to a composting matrix to be determined. Recently introduced treatment regulations require 100% of the waste in a composting system to be maintained above 60 or 70 C for minimum periods. Aeration management methods were evaluated that maximise the rate of temperature increase and distribute the heat generated by microbial activity. Managing re-circulated gases between set CO2 limits was demonstrated to an effective method of encouraging rapid temperature increase. Whilst the lowest recirculation rate of 40m3hr l per m3 of compost was required to ensure 100% of the compost matrix in the test rig was greater than 60 C. The research presented in this thesis demonstrates methods that will aid the design and management of any composting system, especially those treating catering waste.
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Owen, Nia Elin. "Effects of increased kerbside provision and materials recovery facility development on recycling rates in a rural community." Thesis, Cardiff University, 2009. http://orca.cf.ac.uk/54763/.
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Traditionally, the UK has relied heavily on landfill as a means of dealing with its MSW, However, the UK waste management industry is undergoing a significant period of change as a result of legislative drivers implemented on an European level. The key driver is the Landfill Directive, which has set targets for the reduction of the quantity of biodegradable waste sent to landfill. This Directive has been implemented in Wales by the Landfill Allowance Scheme (LAS), which essentially sets each local authority an annual tonnage of Biodegradable Municipal Waste (BMW) which it can landfill. Failure to comply with the annual target can result in significant financial penalties which are set at £200 per tonne landfilled over the target. This driver coupled with the ever increasing landfill tax, which is set to increase by £8 per annum, is making alternatives to landfill become more economically viable. As well as these statutory drivers, there are also non-statutory drivers. In Wales, the Welsh Assembly Government (WAG) issued the non-statutory requirement for local authorities to achieve 40% recycling and composting by 2009/10, with a minimum of 15% recycling and 15% composting. It has also been announced that post 2010, the targets are likely to increase rapidly, culminating in a 70% recycling and composting target by 2024/25. This thesis uses a case study authority to investigate whether a Materials Recovery Facility (MRF) coupled with changes to its kerbside provision could assist the region to meet its LAS and WAG targets. Key aspects of the thesis include: a compositional analysis of household waste within the case study authority, to ascertain the quantities of material available for diversion via a dry recyclate and organics collection scheme a review of a variety of different MRFs within the UK and overseas to determine best practice operations the development of a MRF conceptual design based on the information obtained from compositional analysis and the process reviews conducted on other MRFs the efficiency testing of the MRF commissioned within the case study authority to determine its performance and areas which could be improved and, the modelling of various scenarios to determine what changes could be made to waste management practices so as to maximise the quantity of material diverted from landfill, and assist the authority to meet its LAS and WAG targets. The compositional analysis study identified that the average household waste generation within the Case Study Authority was 14.9 kg/hhAvk, which was lower than the Welsh average figure of 17 kg/hh/wk. Participating households typically segregated 4.7 kg/hhAvk and 3.0 kg/hh/wk of dry recyclate and organic material respectively. It was also interesting to note that the compositional analysis established that the average BMW content within the Case Study Authority was 72%, which was significantly higher than the 61% used to define MSW for the LAS purposes. An efficiency study carried out on the first phase of the MRF implementation highlighted that when processing a residual waste (black bag) stream 11.2% was recovered in the form of dry recyclate, and 27.7% in the form of a mechanically segregated fine organic stream (less than 50mm fraction). When processing a dry recyclate stream, the efficiency study identified that 95% of the material was recovered for recycling however, two-thirds of this was in the form of a low grade paper product, which was sensitive to market changes. The thesis highlights that a MRF has a significant role to play in an integrated solution for municipal waste management however, it is clear that ultimately some form of thermal process will be required for the residual waste stream in order for local authorities to comply with the LAS targets.
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Notton, David. "Theoretical and experimental determination of key operating parameters for composting systems." Thesis, Cardiff University, 2005. http://orca.cf.ac.uk/54547/.
Full textAbstract:
The combination of increasing quantities of Municipal Solid Waste (MSW) and increased legislation for the disposal of this type of waste have created a need to develop different disposal or treatment routes for waste. Approximately 60% of MSW by mass is biodegradable and many disposal routes for this waste allow energy recovery. However the waste hierarchy presented in the National Waste Strategy for Wales emphasises the importance of materials recovery over energy recovery. It has been shown that the only way to achieve these targets is through the recovery of catering waste, which requires an in-vessel composting facility. In order to gain an insight into the aeration requirements for in-vessel composting, calculations were performed to ascertain the required airflow for the supply of oxygen, the removal of excess moisture and the removal of excess heat. It was found that approximately 450kJ are released for each mole of oxygen utilised whilst 500kJ are released per mole of carbon dioxide evolved. It was found that the air requirement for removal of heat from the process was approximately 100 times greater than the air required to supply oxygen to the system. In order to determine the power of aeration equipment required for composting facilities a static pressure test rig was constructed. From the results gained a model relating the static pressure to the bulk density of compost was developed. Initially a windrow composting system processing green waste at the Carmarthenshire Environmental Resources Trust (CERT) composting facility was studied. A canopy system was developed to monitor the respiration rate of this system and allow comparison between different feedstocks and control strategies. For a green waste only windrow the highest recorded respiration rate was 38gC02kgVS"1day"1. The respiration rate was observed to reduce with temperature above 55 °C. In addition to the green waste windrows a temperature managed windrow and a windrow constructed from a mixture of green waste and chicken litter were also tested. The final series of trials involved the testing of the ability of a containerised composting system to meet the Animal By-Products Regulations. The vessel was fed various mixtures of green waste and factory waste. Airflow and insulation within the vessel were analysed and a composting rate of over 45gC02kgVS'1day1 was achieved. If this had been sustained then the vessel may have met the Animal By-Products Regulations.
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Woollam, Tom. "Increasing the diversion of household waste through kerbside recycling systems." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/56072/.
Full textAbstract:
Kerbside recycling schemes in the UK are voluntary. In 2003/4, 61% of households in Wales had some form of kerbside recycling scheme collecting at least one material. Householders are encouraged in a variety of ways to segregate targeted recyclables from their general waste and to put this at the kerbside in any number of separate receptacles. There are many ways of increasing the diversion of household waste into kerbside recycling systems. A plethora of incentives, penalties and communications can be offered and many awareness raising schemes can be employed. This thesis uses a case study authority to trial, then subsequently examine the effectiveness of specific methods to increase the diversion of household waste into kerbside recycling systems. A public waste awareness campaign and a schools waste education programme are implemented within the authority a range of incentives were used, some using voluntary approaches and others financial carrots. Key aspects of the work include a legislative overview of household waste in Wales, a quantitative examination of the scale of the household waste problem and a study of attitudes towards waste, actual recycling behaviour and the effectiveness of a waste awareness campaign and a schools waste education programme. It is thought local authorities which implement kerbside recycling and composting schemes, and still have significant tonnage to divert to meet their 2010 diversion targets, will not meet them by implementing voluntary/carrots and financial/carrots incentives alone. Ultimately, alternative waste treatment technologies that do not require households to participate in segregation or a significant change in kerbside recycling behaviour (thought only possible through financial/stick incentives or alternate weekly collections) will be needed for local authorities to meet the 2010 Wales Waste Strategy targets and reach the required BMW diversion set in the Landfill Allowance Scheme. Waste awareness campaigns and schools education campaigns have a role to play, but, should not be solely relied on to meet short term diversion targets.
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Cowie, Claire. "The use of rhizogenic 'Agrobacterium' strains to improve phytoremediation of inorganic and organic pollutants." Thesis, University of Newcastle Upon Tyne, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436167.
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Adelopo, Abdulganiyu Omobolaji. "Conversion of landfill composite to activated carbon as an approach to sustainable landfill management." Thesis, De Montfort University, 2017. http://hdl.handle.net/2086/14532.
Full textAbstract:
Landfilling of municipal solid waste is a major waste disposal method, especially in developing countries despite its pressing environmental challenges. Reuse of the landfill composite has been suggested as a sustainable management option that could limit its negative effect. This research evaluated the compositional trend and characteristics of landfill composites with depth in order to assess its suitability as a precursor for activated carbon. A bulk system classification was used during analysis of the composite parameters (‘more degraded’ and ‘less degraded’ components). Both landfills had similar waste constituents, but varied in relation to moisture, TOC, and heavy metals contents. The elemental and chemical constituents of an active and a closed landfill were compared using Fourier transform - infrared (FTIR) spectroscopy, scanning electron microscope/energy-dispersive X-ray (SEM/EDX) spectroscopy, and proximate analysis. The two landfills had similar major elemental constituents representing 96.5 % and 98.4 % of elemental composition for the closed (O > C > Si> Fe > Ca >Al) and active(C > O > Si > Al > Ca > Fe) landfill samples respectively. A single step chemical activation process of precursor was applied involving irradiation with microwave energy and KOH as the activation agent. The average percentage yield of activated carbon (AC) from active landfill precursor was higher than that from closed landfill for all three depths of sampling (upper, 23.8 and 19.3 %; mid, 52.4 and 34.7 %; lower 35.7 and 27.0 %). Methylene blue adsorption capacity and BET surface analysis indicated adsorption capacity and surface area of AC from degraded precursor increased with depth. All AC conformed to a multilayer adsorption model and a pseudo second order kinetic. Carbonyl and hydroxyl groups were the major functional group on the surface of activated carbon. The AC properties indicated that precursors from both landfills are potentially suitable for generation of adsorbent suitable for removal of cationic dyes and pollutants.
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Mohammed, Alya. "Development of an engineered wetland system for sustainable landfill leachate treatment." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/105531/.
Full textAbstract:
Sustainable and effective treatment of landfill leachate has become one of the most important environmental problems due to the fluctuating composition and quantity, as well as its high concentrations of pollutants. High-tech solutions applied for the leachate treatment are expensive and energy consuming, and in addition they are not suitable at many landfill sites, especially those in rural areas. Hence there is need to develop novel and sustainable low-energy systems for the effective treatment of landfill leachates. Constructed wetlands (CWs) are inexpensive simple to operate and they have the potential to remove not only organic carbon and nitrogen compounds, but heavy metals. This study focussed on the design, development and experimental investigation of a novel CWs for the treatment of landfill leachate. The CWs employed dewatered ferric waterworks sludge (DFWS) as the main substrate. The overall aim of the study was to design and assess the novel configuration of the CWs, whilst also contributing to advancing the understanding of pollutant removal from the landfill leachate in the CWs, through the development of models to explain the internal processes and predict performance. The key design and operational variables investigated were: the primary media used, i.e. the DFWS, and the wetting and drying regimes. The CWs was configured as 4-stages in series which was operated for 220 days. Thereafter, an additional unit was added due to clogging and the CWs was operated for 185 days in this second period. Results and experimental observations indicate that the chemical treatment processes (adsorption and precipitation) contributed to the clogging. The DFWS used served as adsorbent for heavy metals removal in the system. Results of heavy metals, organic matter (COD), ammonia and total nitrogen removal indicate average removals of 99%, 62%, 83% and 81%, respectively in first period; and 100%, 86%, 90% and 82% in second period, with an average heavy metals loading rate 0.76 g m-2 day-1, organic loading rate 1070 g m-2 day-1, ammonia loading rate of 178 g m-2 day-1 and total nitrogen loading rate 192 g m-2 day-1. Results were supported through mathematical analysis using STELLA model for heavy metals transformation in CWs and numerical modelling using HYDRUS CW2D, which enhanced understanding of the internal processes for organic matter and nitrogen 4 removal. The result from STELLA modelling showed that up to 90% of the removal of heavy metals was through adsorption, which is highly significant. While HYDRUS CW2D results showed that the main path of nitrogen removal was through simultaneous nitrification and denitrification. Overall, results have shown that CWs design has great potential for reduction of metals and nutrients in landfill leachate. Results of this study can contribute to future CW research and design for landfill leachate treatment, through the increased understanding of long-term pollutant removal in these systems. In time, this may result in the wider application of CWs for landfill leachate treatment to better protect the environment.