12 research outputs found
Drag Reduction of a Modern Straight Truck
A wind tunnel test program was conducted at the Langley Full Scale Tunnel (LFST) to evaluate the performance of five passive drag reduction configurations on a modern straight truck at full scale. Configurations were tested in a build-up fashion with results representing a cumulative effect. Tested configurations include a front valance, a front box fairing, a boat-tail, an ideal side-skirt, and a practical side-skirt. Configurations were evaluated over a nominal 9 degree yaw sweep to establish wind averaged drag coefficients using SAE J1252. Genuine replicate yaw sweeps were used in an uncertainty analysis. Results show up to 28% improvement in wind-averaged drag coefficient and that significant gains can be made in straight truck fuel economy, even at non-highway speeds. © 2011 SAE International
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Outcomes in patients with gunshot wounds to the brain.
Introduction:Gunshot wounds to the brain (GSWB) confer high lethality and uncertain recovery. It is unclear which patients benefit from aggressive resuscitation, and furthermore whether patients with GSWB undergoing cardiopulmonary resuscitation (CPR) have potential for survival or organ donation. Therefore, we sought to determine the rates of survival and organ donation, as well as identify factors associated with both outcomes in patients with GSWB undergoing CPR. Methods:We performed a retrospective, multicenter study at 25 US trauma centers including dates between June 1, 2011 and December 31, 2017. Patients were included if they suffered isolated GSWB and required CPR at a referring hospital, in the field, or in the trauma resuscitation room. Patients were excluded for significant torso or extremity injuries, or if pregnant. Binomial regression models were used to determine predictors of survival/organ donation. Results:825 patients met study criteria; the majority were male (87.6%) with a mean age of 36.5 years. Most (67%) underwent CPR in the field and 2.1% (n=17) survived to discharge. Of the non-survivors, 17.5% (n=141) were considered eligible donors, with a donation rate of 58.9% (n=83) in this group. Regression models found several predictors of survival. Hormone replacement was predictive of both survival and organ donation. Conclusion:We found that GSWB requiring CPR during trauma resuscitation was associated with a 2.1% survival rate and overall organ donation rate of 10.3%. Several factors appear to be favorably associated with survival, although predictions are uncertain due to the low number of survivors in this patient population. Hormone replacement was predictive of both survival and organ donation. These results are a starting point for determining appropriate treatment algorithms for this devastating clinical condition. Level of evidence:Level II
Capacity analysis and throughput increase of an automated robotic fastening system
Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, in conjunction with the Leaders for Global Operations Program at MIT, 2017.Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, in conjunction with the Leaders for Global Operations Program at MIT, 2017.Cataloged from PDF version of thesis.Includes bibliographical references (pages 97-101).Large Structure Manufacturing (LSM) is in the midst of implementing a new robotic fastening system that has been designed with flexibility as a key feature. This thesis describes work done build a model of the new system in order to estimate the capacity of the system. It then presents several recommendations to increase the throughput of the system. Additionally, lessons learned from this work are presented so they can be applied to future automation projects.by Matthew John Cragun.M.B.A.S.M
Predictors of Opposition to and Support for the Ordination of Women: Insights from the LDS Church
Female ordination is an important component of gender equality in Christian religious communities. While prior research has examined societal, institutional, and organisational factors that predict changes in ordination policies in Christian denominations, there is very little research examining individuals’ attitudes regarding the ordination of women. In this research, we use data from two surveys of members of The Church of Jesus Christ of Latter-day Saints (LDS) to examine the factors that predict attitudes towards the ordination of women using two polity-specific measures of support or opposition. Results indicate greater support for the ordination of women when framed in a way that takes into account LDS church governance. While several demographic variables predict attitudes towards ordination, the strongest correlate is perceptions of inequality
FGFR2 point mutations in 466 endometrioid endometrial tumors: Relationship with MSI, KRAS, PIK3CA, CTNNB1 mutations and clinicopathological features
Mutations in multiple oncogenes including KRAS, CTNNB1, PIK3CA and FGFR2 have been identified in endometrial cancer. The aim of this study was to provide insight into the clinicopathological features associated with patterns of mutation in these genes, a necessary step in planning targeted therapies for endometrial cancer. 466 endometrioid endometrial tumors were tested for mutations in FGFR2, KRAS, CTNNB1, and PIK3CA. The relationships between mutation status, tumor microsatellite instability (MSI) and clinicopathological features including overall survival (OS) and disease-free survival (DFS) were evaluated using Kaplan-Meier survival analysis and Cox proportional hazard models. Mutations were identified in FGFR2 (48/466); KRAS (87/464); CTNNB1 (88/454) and PIK3CA (104/464). KRAS and FGFR2 mutations were significantly more common, and CTNNB1 mutations less common, in MSI positive tumors. KRAS and FGFR2 occurred in a near mutually exclusive pattern (p = 0.05) and, surprisingly, mutations in KRAS and CTNNB1 also occurred in a near mutually exclusive pattern (p = 0.0002). Multivariate analysis revealed that mutation in KRAS and FGFR2 showed a trend (p = 0.06) towards longer and shorter DFS, respectively. In the 386 patients with early stage disease (stage I and II), FGFR2 mutation was significantly associated with shorter DFS (HR = 3.24; 95% confidence interval, CI, 1.35-7.77; p = 0.008) and OS (HR = 2.00; 95% CI 1.09-3.65; p = 0.025) and KRAS was associated with longer DFS (HR = 0.23; 95% CI 0.05-0.97; p = 0.045). In conclusion, although KRAS and FGFR2 mutations share similar activation of the MAPK pathway, our data suggest very different roles in tumor biology. This has implications for the implementation of anti-FGFR or anti-MEK biologic therapies
The Risk of Lymph Node Metastasis With Positive Peritoneal Cytology in Endometrial Cancer
Infection after penetrating brain injury—An Eastern Association for the Surgery of Trauma multicenter study oral presentation at the 32nd annual meeting of the Eastern Association for the Surgery of Trauma, January 15–19, 2019, in Austin, Texas
2019 EAST PODIUM PAPER Infection after penetrating brain injury—An Eastern Association for the Surgery of Trauma multicenter study oral presentation at the 32nd annual meeting of the Eastern Association for the Surgery of Trauma, January 15–19, 2019, in Austin, Texas Harmon, Laura A. MD; Haase, Daniel J. MD; Kufera, Joseph A. MA; Adnan, Sakib BS; Cabral, Donna BNS; Lottenberg, Lawrence MD; Cunningham, Kyle W. MD, MPH; Bonne, Stephanie MD; Burgess, Jessica MD; Etheridge, James MD; Rehbein, Jennifer L. MD; Semon, Gregory DO; Noorbakhsh, Matthew R. MD; Cragun, Benjamin N. MD; Agrawal, Vaidehi PhD; Truitt, Michael MD; Marcotte, Joseph MD; Goldenberg, Anna DO; Behbahaninia, Milad MD; Keric, Natasha MD; Hammer, Peter M. MD; Nahmias, Jeffry MD; Grigorian, Areg MD; Turay, Dave MD; Chakravarthy, Vikram MD; Lalchandani, Priti MD; Kim, Dennis MD; Chapin, Trinette; Dunn, Julie MD; Portillo, Victor MD; Schroeppel, Thomas MD, MS; Stein, Deborah M. MD, MPH Author Information Journal of Trauma and Acute Care Surgery 87(1):p 61-67, July 2019. | DOI: 10.1097/TA.0000000000002327 Buy CME Test Erratum Abstract BACKGROUND
Fatality rates following penetrating traumatic brain injury (pTBI) are extremely high and survivors are often left with significant disability. Infection following pTBI is associated with worse morbidity. The modern rates of central nervous system infections (INF) in civilian survivors are unknown. This study sought to determine the rate of and risk factors for INF following pTBI and to determine the impact of antibiotic prophylaxis. METHODS
Seventeen institutions submitted adult patients with pTBI and survival of more than 72 hours from 2006 to 2016. Patients were stratified by the presence or absence of infection and the use or omission of prophylactic antibiotics. Study was powered at 85% to detect a difference in infection rate of 5%. Primary endpoint was the impact of prophylactic antibiotics on INF. Mantel-Haenszel χ2 and Wilcoxon\u27s rank-sum tests were used to compare categorical and nonparametric variables. Significance greater than p = 0.2 was included in a logistic regression adjusted for center. RESULTS
Seven hundred sixty-three patients with pTBI were identified over 11 years. 7% (n = 51) of patients developed an INF. Sixty-six percent of INF patients received prophylactic antibiotics. Sixty-two percent of all patients received one dose or greater of prophylactic antibiotics and 50% of patients received extended antibiotics. Degree of dural penetration did not appear to impact the incidence of INF (p = 0.8) nor did trajectory through the oropharynx (p = 0.18). Controlling for other variables, there was no statistically significant difference in INF with the use of prophylactic antibiotics (p = 0.5). Infection was higher in patients with intracerebral pressure monitors (4% vs. 12%; p = \u3c0.001) and in patients with surgical intervention (10% vs. 3%; p \u3c 0.001). CONCLUSION
There is no reduction in INF with prophylactic antibiotics in pTBI. Surgical intervention and invasive intracerebral pressure monitoring appear to be risk factors for INF regardless of prophylactic use. LEVEL OF EVIDENCE
Therapeutic, level IV
Infection after penetrating brain injury—An Eastern Association for the Surgery of Trauma multicenter study oral presentation at the 32nd annual meeting of the Eastern Association for the Surgery of Trauma, January 15–19, 2019, in Austin, Texas
2019 EAST PODIUM PAPER Infection after penetrating brain injury—An Eastern Association for the Surgery of Trauma multicenter study oral presentation at the 32nd annual meeting of the Eastern Association for the Surgery of Trauma, January 15–19, 2019, in Austin, Texas Harmon, Laura A. MD; Haase, Daniel J. MD; Kufera, Joseph A. MA; Adnan, Sakib BS; Cabral, Donna BNS; Lottenberg, Lawrence MD; Cunningham, Kyle W. MD, MPH; Bonne, Stephanie MD; Burgess, Jessica MD; Etheridge, James MD; Rehbein, Jennifer L. MD; Semon, Gregory DO; Noorbakhsh, Matthew R. MD; Cragun, Benjamin N. MD; Agrawal, Vaidehi PhD; Truitt, Michael MD; Marcotte, Joseph MD; Goldenberg, Anna DO; Behbahaninia, Milad MD; Keric, Natasha MD; Hammer, Peter M. MD; Nahmias, Jeffry MD; Grigorian, Areg MD; Turay, Dave MD; Chakravarthy, Vikram MD; Lalchandani, Priti MD; Kim, Dennis MD; Chapin, Trinette; Dunn, Julie MD; Portillo, Victor MD; Schroeppel, Thomas MD, MS; Stein, Deborah M. MD, MPH Author Information Journal of Trauma and Acute Care Surgery 87(1):p 61-67, July 2019. | DOI: 10.1097/TA.0000000000002327 Buy CME Test Erratum Abstract BACKGROUND
Fatality rates following penetrating traumatic brain injury (pTBI) are extremely high and survivors are often left with significant disability. Infection following pTBI is associated with worse morbidity. The modern rates of central nervous system infections (INF) in civilian survivors are unknown. This study sought to determine the rate of and risk factors for INF following pTBI and to determine the impact of antibiotic prophylaxis. METHODS
Seventeen institutions submitted adult patients with pTBI and survival of more than 72 hours from 2006 to 2016. Patients were stratified by the presence or absence of infection and the use or omission of prophylactic antibiotics. Study was powered at 85% to detect a difference in infection rate of 5%. Primary endpoint was the impact of prophylactic antibiotics on INF. Mantel-Haenszel χ2 and Wilcoxon\u27s rank-sum tests were used to compare categorical and nonparametric variables. Significance greater than p = 0.2 was included in a logistic regression adjusted for center. RESULTS
Seven hundred sixty-three patients with pTBI were identified over 11 years. 7% (n = 51) of patients developed an INF. Sixty-six percent of INF patients received prophylactic antibiotics. Sixty-two percent of all patients received one dose or greater of prophylactic antibiotics and 50% of patients received extended antibiotics. Degree of dural penetration did not appear to impact the incidence of INF (p = 0.8) nor did trajectory through the oropharynx (p = 0.18). Controlling for other variables, there was no statistically significant difference in INF with the use of prophylactic antibiotics (p = 0.5). Infection was higher in patients with intracerebral pressure monitors (4% vs. 12%; p = \u3c0.001) and in patients with surgical intervention (10% vs. 3%; p \u3c 0.001). CONCLUSION
There is no reduction in INF with prophylactic antibiotics in pTBI. Surgical intervention and invasive intracerebral pressure monitoring appear to be risk factors for INF regardless of prophylactic use. LEVEL OF EVIDENCE
Therapeutic, level IV
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Outcomes in patients with gunshot wounds to the brain.
INTRODUCTION: Gunshot wounds to the brain (GSWB) confer high lethality and uncertain recovery. It is unclear which patients benefit from aggressive resuscitation, and furthermore whether patients with GSWB undergoing cardiopulmonary resuscitation (CPR) have potential for survival or organ donation. Therefore, we sought to determine the rates of survival and organ donation, as well as identify factors associated with both outcomes in patients with GSWB undergoing CPR. METHODS: We performed a retrospective, multicenter study at 25 US trauma centers including dates between June 1, 2011 and December 31, 2017. Patients were included if they suffered isolated GSWB and required CPR at a referring hospital, in the field, or in the trauma resuscitation room. Patients were excluded for significant torso or extremity injuries, or if pregnant. Binomial regression models were used to determine predictors of survival/organ donation. RESULTS: 825 patients met study criteria; the majority were male (87.6%) with a mean age of 36.5 years. Most (67%) underwent CPR in the field and 2.1% (n=17) survived to discharge. Of the non-survivors, 17.5% (n=141) were considered eligible donors, with a donation rate of 58.9% (n=83) in this group. Regression models found several predictors of survival. Hormone replacement was predictive of both survival and organ donation. CONCLUSION: We found that GSWB requiring CPR during trauma resuscitation was associated with a 2.1% survival rate and overall organ donation rate of 10.3%. Several factors appear to be favorably associated with survival, although predictions are uncertain due to the low number of survivors in this patient population. Hormone replacement was predictive of both survival and organ donation. These results are a starting point for determining appropriate treatment algorithms for this devastating clinical condition. LEVEL OF EVIDENCE: Level II
Genotype-Phenotype Analysis in Congenital Adrenal Hyperplasia due to P450 Oxidoreductase Deficiency
Context: P450 oxidoreductase deficiency (PORD) is a unique congenital adrenal hyperplasia variant that manifests with glucocorticoid deficiency, disordered sex development (DSD), and skeletal malformations. No comprehensive data on genotype-phenotype correlations in Caucasian patients are available.
Objective: The objective of the study was to establish genotype-phenotype correlations in a large PORD cohort.
Design: The design of the study was the clinical, biochemical, and genetic assessment including multiplex ligation-dependent probe amplification (MLPA) in 30 PORD patients from 11 countries.
Results: We identified 23 P450 oxidoreductase (POR) mutations (14 novel) including an exonic deletion and a partial duplication detected by MLPA. Only 22% of unrelated patients carried homozygous POR mutations. p.A287P was the most common mutation (43% of unrelated alleles); no other hot spot was identified. Urinary steroid profiling showed characteristic PORD metabolomes with variable impairment of 17α-hydroxylase and 21-hydroxylase. Short cosyntropin testing revealed adrenal insufficiency in 89%. DSD was present in 15 of 18 46,XX and seven of 12 46,XY individuals. Homozygosity for p.A287P was invariably associated with 46,XX DSD but normal genitalia in 46,XY individuals. The majority of patients with mild to moderate skeletal malformations, assessed by a novel scoring system, were compound heterozygous for missense mutations, whereas nearly all patients with severe malformations carried a major loss-of-function defect on one of the affected alleles.
Conclusions: We report clinical, biochemical, and genetic findings in a large PORD cohort and show that MLPA is a useful addition to POR mutation analysis. Homozygosity for the most frequent mutation in Caucasians, p.A287P, allows for prediction of genital phenotype and moderate malformations. Adrenal insufficiency is frequent, easily overlooked, but readily detected by cosyntropin testing