The Effect of Repeated Recycling at Different Levels of Addition (Virgin and Recycled Fiber) on the Surface Characteristic of Paper Before and After Calendering

Extensive work has been done on the physical properties of paper with recycling, however not much has been researched on the surface properties of paper. This thesis was intended to give more information on this fairly untouched area. An extra dimension was added with the inclusion of virgin fibers. Two loops were designed, one using the conventional 100% recycled fibers and the other, with an addition of virgin pulp. 100% never dried kraft hardwood, refined at 300 CSF, was used. All handsheets were made on the Nobel and Wood handsheet-maker and repeated reslushing was performed on the British Disintegrator. No additives, fillers, or sizing agents were used at any point, thus, recycling was only subjected to: slushing, sheet making, wet-pressing and drying. Calendering was also performed. The principal effect of recycling was the loss of the fiber bonding ability, noticeably in the first recycle for opacity and porosity (100% recycle). The addition of virgin fibers was interestingly seen to improve the brightness with recycling. This phenomena (an increase in brightness with the addition of virgin fibers in comparison to the original brightness) has to be further investigated. Calendering with its compacting and polishing action, decreased the opacity and increased the smoothness. Roughness and gloss did not show a significant change with recycling but with calendering a more smoother and glossier sheet was obtained, as expected

Traditional fuels and cooking stoves in developing countries: a technical, social and environmental assessment

Population pressure in developing countries is believed to be the predominant cause of deforestation, due to the dual needs of food and fuel. This has led to a shortage of firewood (for cooking) and affects especially the rural poor of these countries. One intervention strategy to reduce firewood consumption has been to design, develop and disseminate "improved" (ie fuel efficient) cooking stoves for use in the rural sector. These stove programmes have failed to achieve widespread dissemination of "improved" stoves. One reason is the mismatch between the felt needs and problems of the rural poor and the assumptions of institutions and individuals designing and promoting these stoves. Moreover, traditional stoves and fireplaces are not inherently inefficient for cooking. Not all "improved" stoves have been more efficient than traditional designs in practice. Traditional modes of cooking serve a number of sociocultural and practical functions which have been neglected in stove programmes to date. Stove users in a number of developing countries appear to be more concerned about speedy cooking whilst stove programmes overemphasize fuel savings. Villagers in Zimbabwe appear to have spontaneously transferred to stoves which consume significantly more fuel than their traditional fireplace. However, this lack of fuel economy is offset by the benefits of faster cooking, greater space heat, more stable pots and a modern "image". The higher firewood collection costs are affordable as this takes place in the agriculturally slack season. Deforestation is a complex issue to which there are a number of contributary factors. In Zimbabwe, the processes of land degradation, deforestation, and the ensuing shortage of firewood were set in motion as early as the 1890’s when the African population residing on the fertile highlands was forcibly evicted onto marginal land by European settlers. Strategies to cope with deforestation in Zimbabwe would be aided by user participation in defining needs and problems within the wider framework of land tenure, agroforestry schemes and inputs to increase the productivity of African areas

ACTIVITY STUDY OF CU BASED CATALYTIC MATRIXES WITH ZNO AND/OR ZRO2 FOR ENHANCEMENT OF CATALYST ACTIVE LIFETIME AND METHANOL YIELD

A series of Cu/ZnO/Al2O3, Cu/ZnO/ZrO2/Al2O3 and Cu/ZrO2/Al2O3 catalysts were prepared for methanol synthesis study in Lurgi process. Apart from Cu and Al2O3, these catalysts would contain ZnO and/or ZrO2 as active Carbon monoxide (CO) hydrogenation sites. The preparation method was an alternative acid-alkali pH precipitation. The SEM-EDX data for the formulations with various atomic ratios showed high homogeneity, hence good intermixing of ingredients. TPR analysis was done on all prepared matrixes and industrial catalyst and showed the reduction temperature of 300 oC to 345 oC for all 3 types of catalysts prepared. Both Low and High Temperature peak obtained for Metal Surface Area (MSA) analysis showed that there is a general decreasing H2 adsorption trend with the increasing amount of Zirconia in the catalyst. Prepared catalyst sample A with no zirconia present showed highest low and High Temperature adsorption in comparison with commercial and prepared catalysts. This suggests that Cu-ZnO catalyst have higher activity as compared to Cu-Zirconia based catalysts. TGA analysis also reveals that prepared catalysts sample has higher thermal stability at Lurgi Operating Temperature of 250oC compared to Industrial catalysts sample. CO conversion study reveals that sample A with no Zr present has highest conversion of up to 4%. Also determined was that Zn offers higher activity in CO hydrogenation process in catalyst samples compared to Zr when present in the same atomic %. Also monoclinic Zr phase formed in catalyst type Cu/ZnO/ZrO2/Al2O3 gives higher MeOH Yield compared to catalyst sample where tetragonal Zr phase is formed. A consistent trend between CH4 formation during activity study and Carbon formation study by CHNS reveals the most likely route for Carbon formation was through CH4 decomposition to form Carbon on catalysts surface sample The analytical kinetic study conducted decided that coverage of O atoms should be 0.5 in the beginning of the reaction in order to maximize the initial rate of reaction.

Predictors of pain and use of pain medications following primary Total Hip Arthroplasty (THA): 5,707 THAs at 2-years and 3,289 THAs at 5-years

<p>Abstract</p> <p>Background</p> <p>Study pain and use of pain medications and their predictors after primary Total Hip Arthroplasty (THA).</p> <p>Methods</p> <p>We examined whether gender, age (reference, < = 60 yrs), body mass index (BMI; reference, <25 kg/m²)), comorbidity measured by Deyo-Charlson index (5-point increase), anxiety and depression predict moderate-severe hip pain and use of pain medications 2- and 5-years after primary THA. Multivariable logistic regression adjusted for these predictors and distance from medical center, operative diagnosis, American Society of Anesthesiologists (ASA) score and implant type.</p> <p>Results</p> <p>Moderate-severe pain was reported by 8.1% at 2-years and 10.8% at 5-years. Significant predictors of moderate-severe pain at 2-year follow-up were [Odds ratio (95% confidence interval)]: BMI 35-39.9, 1.8 (1.2,2.8); BMI > = 40, 1.7 (1.0,2.9); depression, 2.1 (1.4,3.0). Moderate-severe pain at 5-years was more common in patients with higher BMI: 25-29.9, 1.5 (1.1,2.1); 30-34.9, 1.8 (1.2,2.6); 35-39.9, 1.9 (1.2,3.1); and > = 40, 3.1 (1.7,5.7).</p> <p>Significant predictors of NSAID use were [Odds ratio (95% confidence interval)]: female gender at 2- and 5-years, 1.4 (1.1,1.7) and 1.4 (1.1,1.8); BMI 35-39.9 at 2-years, 1.9 (1.4, 2.6) and 30-34.9 at 2-years, 1.7 (1.2,2.4); and depression at 5-years, 1.8 (1.2,2.8).</p> <p>Significant predictors of opioid medication use were [Odds ratio (95% confidence interval)]: female gender at 2- and 5-years, 2.0 (1.1,3.0) and 2.4 (1.4,4.0); BMI 30-34.9 at 2-years, 2.0 (1.0,3.9); and depression at 2-years, 2.0 (1.1,3.7).</p> <p>Conclusions</p> <p>Higher BMI and depression impacted moderate-severe pain; and female gender, higher BMI and depression predicted use of pain medications at 2- and 5-years post-primary THA.</p

Patients with osteoarthritis and avascular necrosis have better functional outcomes and those with avascular necrosis worse pain outcomes compared to rheumatoid arthritis after primary hip arthroplasty: a cohort study

BACKGROUND: This study was conducted to assess whether patient-reported outcomes (PROs) differ by the underlying diagnosis (rheumatoid arthritis (RA)/inflammatory arthritis, osteoarthritis (OA), avascular necrosis of bone (AVN), other) in patients undergoing primary total hip arthroplasty (THA). METHODS: We used prospectively collected data to assess the association of diagnosis with index hip function and pain. Moderate-severe activity limitation and moderate-severe pain were assessed at two- and five-year follow-up after primary THA using multivariable-adjusted logistic regression analyses. Odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS: There were 5,707 primary THAs at two-years and 3,289 at five-years, 51% were women and the mean age was 65 years. The underlying diagnosis was RA in 3%, OA in 87%, AVN in 7% and other in 3%. In multivariable-adjusted analyses, compared to RA, diagnoses of OA and AVN were significantly associated with lower odds of moderate-severe activities of daily living limitations with an OR (95% CI) of 0.5 (0.3 to 0.8) (P = 0.01) and 0.4 (0.2 to 0.8) (P = 0.01), respectively, at two-years, but not at five-years, 0.7 (0.4 to 1.4) (P = 0.36) and 0.9 (0.4 to 1.8) (P = 0.78), respectively. At two-years, neither OA nor AVN were significantly associated with higher odds of moderate-severe pain (1.6 (0.6 to 4.5) (P = 0.40) and 2.8 (0.9 to 8.5) (P =0 0.06)), respectively. At five-years, AVN was associated with higher odds of moderate-severe pain with OR 4.1 (1.2 to 14.1) (P = 0.02), but not OA, 2.1 (0.7 to 6.5) (P = 0.22). CONCLUSIONS: We found that patients with OA and AVN had better functional outcomes and those with AVN worse pain outcomes after primary THA, compared to patients with RA/inflammatory arthritis. Insights into mediators of these relationships are needed to better understand these associations

ACTIVITY STUDY OF CU BASED CATALYTIC MATRIXES WITH ZNO AND/OR ZRO2 FOR ENHANCEMENT OF CATALYST ACTIVE LIFETIME AND METHANOL YIELD

A series of Cu/ZnO/Al2O3, Cu/ZnO/ZrO2/Al2O3 and Cu/ZrO2/Al2O3 catalysts were prepared for methanol synthesis study in Lurgi process. Apart from Cu and Al2O3, these catalysts would contain ZnO and/or ZrO2 as active Carbon monoxide (CO) hydrogenation sites. The preparation method was an alternative acid-alkali pH precipitation. The SEM-EDX data for the formulations with various atomic ratios showed high homogeneity, hence good intermixing of ingredients. TPR analysis was done on all prepared matrixes and industrial catalyst and showed the reduction temperature of 300 oC to 345 oC for all 3 types of catalysts prepared. Both Low and High Temperature peak obtained for Metal Surface Area (MSA) analysis showed that there is a general decreasing H2 adsorption trend with the increasing amount of Zirconia in the catalyst. Prepared catalyst sample A with no zirconia present showed highest low and High Temperature adsorption in comparison with commercial and prepared catalysts. This suggests that Cu-ZnO catalyst have higher activity as compared to Cu-Zirconia based catalysts. TGA analysis also reveals that prepared catalysts sample has higher thermal stability at Lurgi Operating Temperature of 250oC compared to Industrial catalysts sample. CO conversion study reveals that sample A with no Zr present has highest conversion of up to 4%. Also determined was that Zn offers higher activity in CO hydrogenation process in catalyst samples compared to Zr when present in the same atomic %. Also monoclinic Zr phase formed in catalyst type Cu/ZnO/ZrO2/Al2O3 gives higher MeOH Yield compared to catalyst sample where tetragonal Zr phase is formed. A consistent trend between CH4 formation during activity study and Carbon formation study by CHNS reveals the most likely route for Carbon formation was through CH4 decomposition to form Carbon on catalysts surface sample The analytical kinetic study conducted decided that coverage of O atoms should be 0.5 in the beginning of the reaction in order to maximize the initial rate of reaction.

Učinkovitost zatvaranja sisnih kanala kao prevencija novih intramamarnih infekcija u mliječnih krava tijekom suhostaja

The aim of our study was to evaluate the effect of an internal teat sealant infused upon drying off on the incidence of new intra-mammary infections (IMI) during the dry period in dairy cattle. Due to the non-availability of the product on the Indian market, the product was prepared in a laboratory using bismuth subnitrate and liquid paraffin. A total of 64 quarters free from infection on culture were selected for the study at 60 days before the expected date of parturition. The quarters were randomly divided into two groups (group A and group B), with 32 quarters in each group. The group A quarters were infused with teat sealant at the time of drying off, and the quarters in group B were kept as the control and no treatment was provided to them. Milk samples from all the selected quarters were subjected to cultural examination at the time of drying off and 1-3 days post calving. The incidence of new IMI’s between drying off and calving was significantly lower for group A quarters when compared to group B quarters (12.5% vs 34.4%). The incidence of new IMI’s in group A and group B quarters was significantly lower for Streptococcus uberis (3.13% vs 18.75%) and Streptococcus dysgalactiae (3.13% vs 12.5%). The study concluded that infusion of teat sealant at drying off is helpful in lowering the incidence of new IMI’s during the dry period.Cilj ovog istraživanja bio je procijeniti učinak zatvaranja sisnih kanala na incidenciju infekcija vimena (IMI) mliječnih krava za vrijeme suhostaja. Zbog nedostupnosti komercijalnih preparata na indijskom tržištu, proizvod za zatvaranje sisnih kanala je pripravljen u laboratoriju upotrebom bizmut-subnitrata i tekućeg parafina. Za istraživanje su odabrane 64 četvrti vimena u kojima bakteriološkom kulturom nije bilo utvrđene infekcije 60 dana prije očekivanog teljenja. Četvrti su nasumično podijeljene u dvije skupine (skupina A i skupina B) sa po 32 četvrti u svakoj skupini. U skupini A, tijekom suhostaja, kravama su zatvoreni sisni kanali, dok u kontrolnoj skupini B nije proveden nikakav tretman. Uzorci mlijeka iz svih skupina podvrgnuti su testiranju bakteriološkom kulturom u vrijeme suhostaja i 1 – 3 dana poslije teljenja. Incidencija intramamarnih infekcija između suhostaja i teljenja bila je znakovito niža u skupini A u usporedbi sa skupinom B (12,5 % prema 34,4 %). Incidencija novih intramamarnih infekcija u skupinama A i B bila je znakovito niža za Streptococcus uberis (3,13 % prema 18,75 %) i Streptococcus dysgalactiae (3,13 % prema 12,5 %). Rezultati istraživanja pokazuju da zatvaranje sisnih kanala u suhostaju pomaže u smanjivanju incidencije novih intramamarnih infekcija