Search

Newregulations by the California Air Resources Board (CARB) demand a stringent 0.02 g/hp-hr tailpipe NOx limit by the year 2027, requiring Selective Catalytic Reduction (SCR) catalysts to provide high NOx conversions even at low (below 200°C) exhaust temperatures. This work describes utilizing an Electrically Heated Mixer System(EHMsystem) upstreamof a Light-Off SelectiveCatalytic Reduction (LO-SCR) catalyst followed by a conventional aftertreatment (AT) system containing DOC, DPF, and SCR, enabling high NOx conversions meeting CARB's NOx emission target. The AT catalysts were hydrothermally aged to Full Useful Life. Conventional unheated Diesel Exhaust Fluid (DEF) was injected upstream of both the LO-SCR and primary downstream SCR. The EHM system allowed for DEF to be injected as low as 130°C upstream of the LO-SCR, whereas, in previous studies, unheated DEF was injected at 180°C or dosed at 130°Cwith heatedDEF. The combination of unheated DEF, EHMsystem, LO-SCR, and downstream SCR enabled the needed increase in NOx efficiency in low exhaust temperatures, which was observed in drive cycles such as in cold-FTP, LLC, and World Harmonized Transient Cycle (WHTC). There were severalfold reductions in tailpipe NOx using this configuration compared to its baseline: 3.3-fold reduction in FTP, 22-fold in Low Load Cycle (LLC), 38-fold in Beverage Cycle, 8-fold in "Stay Hot" Cycle, and 10-fold inWHTC. Finally, it is shown that the EHM system can heat the exhaust gas, such as during a cold start, without needing additional heating hardware integrated into the system. These results were observed without performing changes in the engine base calibration. [ABSTRACT FROM AUTHOR]

Since the introduction of diesel urea SCR technology, aftertreatment thermal management has become critical for maintaining SCR catalyst light-off and thereby low cumulative cycle NOx emissions. A novel diesel engine aftertreatment thermal management strategy is proposed which utilizes a 2-stroke breathing variable value actuation strategy to increase the mass flow rate of exhaust gas. Experiments showed that when emissions are constrained to the same level as a state-of-the-art thermal management strategy, 2SB does not increase heat transfer to aftertreatment. However, if constraints are allowed to flex, temperatures comparable to a state-of-the-art thermal management calibration could be achieved with a 1.75× exhaust mass flow rate, potentially helping heat the SCR catalyst in a cold-start scenario. [ABSTRACT FROM AUTHOR]

Low air-flow diesel engine strategies are advantageous during low load operation to maintain temperatures of a warmed-up aftertreatment system (ATS) while reducing fuel consumption and engine-out emissions. This paper presents results at curb idle for internal EGR (iEGR) that demonstrate low airflow and reduced engine-out emissions during fuel-efficient ATS temperature maintenance operation. Internal EGR via reinduction and trapping using negative valve overlap (NVO) are compared to each other, conventional operation and to other low airflow approaches including cylinder deactivation (CDA). At 800 RPM/1.3 bar BMEP (curb idle) iEGR via reinduction enables 200°C engine-out temperature combined with 70% lower NO X , 35% lower fuel consumption, and 40% lower exhaust flow rate than conventional thermal management operation. Internal EGR via trapping using NVO resulted in an engine-out temperature of 185°C, with 56% lower NO X and 25% lower fuel consumption than conventional thermal management operation. Both iEGR strategies have lower engine-out temperatures and higher exhaust flow rates than CDA. No external EGR is required for either iEGR strategy. "iEGR via reinduction" outperforms "iEGR via NVO" as a result of higher open cycle efficiency (via less pumping work) and higher closed-cycle efficiency (via higher specific heat ratio). [ABSTRACT FROM AUTHOR]

Burnout remains an emerging challenge in healthcare. Burnout in these settings has been associated with compromised personal wellbeing, decreased work productivity, higher healthcare costs, decreased patient satisfaction, and deteriorating quality of patient care. As pharmacist roles on healthcare teams expand, health-system pharmacy leaders should be cognizant of burnout, including risk factors and identification. Coordinated efforts should foster pharmacist wellbeing and resilience, individualized work-related responsibilities to ensure professional ambitions are met, promotion of upper leadership expectation transparency, and cultivation of relationships within the pharmacy department. [ABSTRACT FROM AUTHOR]

Modern diesel engine aftertreatment systems require elevated temperatures for effective reduction of engine-out emissions. Maintaining elevated aftertreatment temperatures in a fuel-efficient manner is a challenge, especially at low-load engine operation where engine-outlet temperatures are low; therefore, higher engine-outlet temperatures are typically achieved via increased fuel consumption. Previous studies have demonstrated that strategies such as cylinder deactivation (method where there is neither valve motion nor fuel injection in a subset of cylinders, thereby isolating the deactivated cylinders from the gas exchange process) and cylinder cutout (method where there is no fuel injection in a subset of cylinders, implemented with high recirculated gas rates) reduce fuel consumption while elevating engine-outlet temperatures, by reducing the overall airflow through the engine. This article introduces and characterizes ‘‘non-fired cylinder ventilation’’ as alternate means to achieve fuel-efficient aftertreatment thermal management, by reduction of overall airflow through the engine. Fuel injection is deactivated from a subset of cylinders during non-fired cylinder ventilation, and the non-firing cylinders participate in the gas exchange process with the same manifold at a time, thereby reducing the intake-to-exhaust manifold gas exchange through the cylinders. It is demonstrated that non-fired cylinder ventilation shows similar fuel efficiency and thermal management as cylinder deactivation when the valves of the non-firing ventilated cylinders are open by at least 4 mm, due to similar, negligible, gas-exchange losses, while non-fired cylinder ventilation with lower valve lifts enables elevated engine-outlet temperatures with relatively higher fuel consumption than cylinder deactivation. Non-fired cylinder ventilation strategies demonstrate 75 °C higher temperatures at fuel-neutral conditions, and up to 35% fuel savings at similar temperatures, compared to six-cylinder operation. [ABSTRACT FROM AUTHOR]

Aftertreatment thermal management is critical for regulating emissions in modern diesel engines. Elevated engine-out temperatures and mass flows are effective at increasing the temperature of an aftertreatment system to enable efficient emission reduction. In this effort, experiments and analysis demonstrated that increasing the idle speed, while maintaining the same idle load, enables improved aftertreatment "warm-up" performance with engine-out NOx and particulate matter levels no higher than a state-of-the-art thermal calibration at conventional idle operation (800 rpm and 1.3 bar brake mean effective pressure). Elevated idle speeds of 1000 and 1200 rpm, compared to conventional idle at 800 rpm, realized 31%-51% increase in exhaust flow and 25 °C-40 °C increase in engine-out temperature, respectively. This study also demonstrated additional engine-out temperature benefits at all three idle speeds considered (800, 1000, and 1200 rpm, without compromising the exhaust flow rates or emissions, by modulating the exhaust valve opening timing. Early exhaust valve opening realizes up to ;51% increase in exhaust flow and 50 °C increase in engine-out temperature relative to conventional idle operation by forcing the engine to work harder via an early blowdown of the exhaust gas. This early blowdown of exhaust gas also reduces the time available for particulate matter oxidization, effectively limiting the ability to elevate engine-out temperatures for the early exhaust valve opening strategy. Alternatively, late exhaust valve opening realizes up to ;51% increase in exhaust flow and 91 °C increase in engine-out temperature relative to conventional idle operation by forcing the engine to work harder to pump in- cylinder gases across a smaller exhaust valve opening. In short, this study demonstrates how increased idle speeds, and exhaust valve opening modulation, individually or combined, can be used to significantly increase the "warm-up" rate of an aftertreatment system. [ABSTRACT FROM AUTHOR]

Cylinder deactivation can be implemented at low loads in diesel engines to improve efficiency and aftertreatment thermal management through reductions in pumping work and airflow, respectively. The rate of increase of torque/power during diesel engine transients is limited by the engine's ability to increase the airflow quickly enough to allow sufficient fuel addition to meet the desired torque/power. The reduced airflow during cylinder deactivation needs to be managed properly so as to not slow the torque/power response. This paper demonstrates that it is possible to operate a diesel engine at low loads in cylinder deactivation without compromising its transient torque/power capabilities, a key finding in enabling the practical implementation of cylinder deactivation in diesel engines. [ABSTRACT FROM AUTHOR]

The article discusses Texas water law as it relates to oil and gas production as of June 2012, focusing on the use of surface water and groundwater in production processes, as well as an overview of the state's Rule of Capture regarding a landowner's right to capture water from his or her land. It states that in several Texas Supreme Court cases, landowners have expressed their reported right to protect groundwater resources from third-party capture.

Objective. In 1999, three randomized controlled trials concluded that high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (HDC/HCT) is no better than conventional chemotherapy for women with breast cancer. This study documents the impact of the trials on use of HDC/HCT and describes how hospitals reacted to the trials. Data Source. We used patient-level data on 15,847 HDC/HCTs reported to the Center for International Blood and Marrow Transplant Research between 1994 and 2005. Study Design. We report trends in total HDC/HCT procedure volume, compare the time to hospitals' exit from the HDC/HCT market between research and nonresearch hospitals, and document trends in hospital-specific volumes in the 2 years before exit. Principal Findings. HDC/HCT volume declined from 3,108 in 1998 to 1,363 the year after trial results were released. In 2002, only 76 procedures were performed. Teaching hospitals and the hospitals that participated in the trials were no slower to discontinue the procedure compared with nonteaching, nonparticipating hospitals. At the hospital level, volume declined steadily in the months before abandonment. Conclusion. The results suggest that comparative effectiveness research studies that report negative results can reduce spending, but specialists may be reluctant to relinquish cutting-edge technologies. [ABSTRACT FROM AUTHOR]

Background: Bone mineral density (BMD) loss commonly occurs after hematopoietic cell transplantation (HCT). Hypothesizing that genetic variants may influence post-HCT BMD loss, we conducted a prospective study to examine the associations of single nucleotide polymorphisms (SNP) in bone metabolism pathways and acute BMD loss after HCT. Methods and Findings: We genotyped 122 SNPs in 45 genes in bone metabolism pathways among 121 autologous and allogeneic HCT patients. BMD changes from pre-HCT to day +100 post-HCT were analyzed in relation to these SNPs in linear regression models. After controlling for clinical risk factors, we identified 16 SNPs associated with spinal or femoral BMD loss following HCT, three of which have been previously implicated in genome-wide association studies of bone phenotypes, including rs2075555 in COL1A1, rs9594738 in RANKL, and rs4870044 in ESR1. When multiple SNPs were considered simultaneously, they explained 5-35% of the variance in post-HCT BMD loss. There was a significant trend between the number of risk alleles and the magnitude of BMD loss, with patients carrying the most risk alleles having the greatest loss. Conclusion: Our data provide the first evidence that common genetic variants play an important role in BMD loss among HCT patients similar to age-related BMD loss in the general population. This infers that the mechanism for post-HCT bone loss is a normal aging process that is accelerated during HCT. A limitation of our study comes from its small patient population; hence future larger studies are warranted to validate our findings. [ABSTRACT FROM AUTHOR]

The slower engraftment kinetics and impaired immune reconstitution of cord blood stem cell transplant recipients increase the risk of infectious complications. We retrospectively reviewed patients who underwent cord blood stem cell transplantation at Roswell Park Cancer Institute for hematological malignancies and who survived beyond day 100 for late infectious events. Among 15 patients who were included in the study, there were 18 episodes of bacteremia, 5 cases of bacterial pneumonia, 9 viral, 4 fungal, and 1 nontuberculous mycobacterial infection. Overall mortality was 60%, with infections contributing in 44% of cases. In conclusion, survival beyond day 100 following cord bloodstem cell transplantation is associated with a considerable risk of infections in our single center experience. [ABSTRACT FROM AUTHOR]

Hypothesis: Inguinal hernia significantly affects family and other informal caregivers, and hernia repair will significantly reduce caregiver burden. Methods: We analyzed data from a Veterans Affairs Cooperative Study with mixed models to compare the level of burden among caregivers of inguinal hernia patients from preoperative measurement to measurement at 2 weeks and at 3 months postoperatively. Results: Most caregivers were wives (73%) and lived with the patients (88%). There were no differences in caregiver burden by type of treatment. The time caregivers spent assisting patients increased significantly over the 2 weeks following treatment (odds ratio, 4.34). In contrast, 3 months after treatment, caregivers reported spending less time on additional chores than before treatment (odds ratio, 0.12). Furthermore, caregivers' concerns about patients' abilities to perform normal household activities decreased by 2 weeks posttreatment (odds ratio, 0.52). Wives/girlfriends and caregivers of patients with complications were more likely to report these concerns. Conclusions: Inguinal hernia and its repair significantly affect informal caregivers. Caregivers assumed the heaviest time and effort-related burden 2 weeks following hernia repair and expended additional effort if the patient experienced complications. Interventions should reflect when burden is greatest and target the subgroups of caregivers who most need support. [ABSTRACT FROM AUTHOR]

Tacrolimus (Prograf®, FK506, Fujisawa Healthcare) is a widely used immunosuppressive agent that is used both for the prevention and treatment of solid organ transplant rejection as well as for the prevention and treatment of graft-versus-host disease after allogeneic blood and marrow transplant. Oral preparations of tacrolimus are commercially available in 0.5, 1 and 5 mg gelatin capsules. Previously, only a 0.5 mg/ml oral suspension has been demonstrated to be stable for use in pediatric patients. On our bone marrow transplant service, we found that using this concentration of tacrolimus led to confusion, with patients and their caregivers confusing milligrams and milliliters, thus increasing errors with this formulation. We postulated that a 1 mg/ml oral formulation of tacrolimus would decrease the potential for medication errors. Our findings support new stability information of approximately 4 months for an extemporaneous oral suspension of tacrolimus at a concentration of 1 mg/ml.Bone Marrow Transplantation (2006) 37, 781–784. doi:10.1038/sj.bmt.1705320; published online 6 March 2006 [ABSTRACT FROM AUTHOR]

The article discusses the treatment of inguinal hernia in men who have minimal symptoms or who are asymptomatic. The study is a multicenter clinical trial in North America, using data from the Short Form-36 Version 2 survey to compare the physical component score (PCS), pain, and other outcomes. The results indicate that, at two years, intention-to-treat outcomes were similar for watchful waiting and surgical repair. The men had been randomly assigned to a watchful-waiting strategy or standard open-tension-free surgery with mesh. The researchers concluded that watchful waiting and delaying surgery until symptoms increase is an acceptable strategy.

Thalidomide has been associated with venous thrombotic events, as reported in the post-marketing surveillance reports by Celgene Corporation; as well as case reports in the literature. Seven arterial thrombotic events have been reported in patients receiving thalidomide with 3 cases occurring in patients with other predisposing conditions. We report 4 additional cases of arterial thromboses in 1 lymphoma and 3 myeloma patients treated with thalidomide. The mechanism for these events is unclear; however, it is significant that 2 patients were receiving concomitant anticoagulation with aspirin and warfarin. [ABSTRACT FROM AUTHOR]

Many challenges emerged during completion of a study to examine radiation dose and acute leukemia among children in areas of the former Soviet Union. In an era of globalization, our experiences might benefit others involved in multinational investigations. [ABSTRACT FROM AUTHOR]

Presents information on a study which determined if the addition of thalidomide would salvage vincristine, adriamycin, dexamethasone-refractory patients and allow them to proceed to autologous peripheral blood stem cell transplantation. Methodology of the study; Results and discussion.

Context: Women with breast cancer are the most frequent recipients of high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (autotransplants) in North America. Despite widespread use, controversy exists about the benefits of and appropriate patients for this therapy.Objective: To determine factors associated with disease progression or death after autotransplantation in women with metastatic breast cancer.Design: Analysis of data collected retrospectively (January 1989 to 1992) and prospectively (1992 through January 1995) for the Autologous Blood and Marrow Transplant Registry.Setting: Sixty-three hospitals in North America, Brazil, and Russia.Participants: A total of 1188 consecutive women aged 18 to 70 years receiving autotransplants for metastatic or locally recurrent breast cancer, with a median follow-up of 291/2 months.Main Outcome Measure: Time to treatment failure (disease progression, disease recurrence, or death) after autotransplantation.Results: Factors associated with significantly (P<.05) increased risk of treatment failure in a Cox multivariate analysis included age older than 45 years (relative hazard, 1.17; 95% confidence interval [CI], 1.02-1.33), Karnofsky performance score less than 90% (1.27; 95% CI, 1.07-1.51), absence of hormone receptors (1.31; 95% CI, 1.15-1.51), prior use of adjuvant chemotherapy (1.31; 95% CI, 1.10-1.56), initial disease-free survival interval after adjuvant treatment of no more than 18 months (1.99; 95% CI, 1.62-2.43), metastases in the liver (1.47; 95% CI, 1.20-1.80) or central nervous system (1.56; 95% CI, 0.99-2.46 [approaches significance]) vs soft tissue, bone, or lung, 3 or more sites of metastatic disease (1.32; 95% CI, 1.13-1.54), and incomplete response vs complete response to standard-dose chemotherapy (1.65; 95% CI, 1.36-1.99). Receiving tamoxifen posttransplantation was associated with a reduced risk of treatment failure in women with hormone receptor-positive tumors (relative hazard, 0.60; 95% CI, 0.47-0.87). Women with no risk factors (n = 38) had a 3-year probability of progression-free survival of 43% (95% CI, 27%-61 %) vs 4% (95% CI, 2%-8%) for women with more than 3 risk factors (n = 343).Conclusion: These data indicate that some women are unlikely to benefit from autotransplantation and should receive this treatment only after being provided with prognostic information and in the context of clinical trials attempting to improve outcome. [ABSTRACT FROM AUTHOR]

Considers how health-related quality of life has not been evaluated as a predictor of mortality following coronary artery bypass graft (CABG) surgery. Study to determine if the Physical and Mental Component Summary scores from the preoperative Short-Form 36 health status survey predict mortality following CABG surgery after adjustment for known clinical risk variables; Design; Setting; Patients; Main outcome measures; Results; Conclusions.