The Momentum Constraints of General Relativity and Spatial Conformal Isometries

Transverse-tracefree (TT-) tensors on $({\bf R}^3,g_{ab})$, with $g_{ab}$ an asymptotically flat metric of fast decay at infinity, are studied. When the source tensor from which these TT tensors are constructed has fast fall-off at infinity, TT tensors allow a multipole-type expansion. When $g_{ab}$ has no conformal Killing vectors (CKV's) it is proven that any finite but otherwise arbitrary set of moments can be realized by a suitable TT tensor. When CKV's exist there are obstructions -- certain (combinations of) moments have to vanish -- which we study.Comment: 16 page

Discrimination of Potent Inhibitors of Toxoplasma gondii Enoyl-Acyl Carrier Protein Reductase by a Thermal Shift Assay

Many microbial pathogens rely on a type II fatty acid synthesis (FASII) pathway that is distinct from the type I pathway found in humans. Enoyl-acyl carrier protein reductase (ENR) is an essential FASII pathway enzyme and the target of a number of antimicrobial drug discovery efforts. The biocide triclosan is established as a potent inhibitor of ENR and has been the starting point for medicinal chemistry studies. We evaluated a series of triclosan analogues for their ability to inhibit the growth of Toxoplasma gondii, a pervasive human pathogen, and its ENR enzyme (TgENR). Several compounds that inhibited TgENR at low nanomolar concentrations were identified but could not be further differentiated because of the limited dynamic range of the TgENR activity assay. Thus, we adapted a thermal shift assay (TSA) to directly measure the dissociation constant (Kd) of the most potent inhibitors identified in this study as well as inhibitors from previous studies. Furthermore, the TSA allowed us to determine the mode of action of these compounds in the presence of the reduced nicotinamide adenine dinucleotide (NADH) or nicotinamide adenine dinucleotide (NAD+) cofactor. We found that all of the inhibitors bind to a TgENR–NAD+ complex but that they differed in their dependence on NAD+ concentration. Ultimately, we were able to identify compounds that bind to the TgENR–NAD+ complex in the low femtomolar range. This shows how TSA data combined with enzyme inhibition, parasite growth inhibition data, and ADMET predictions allow for better discrimination between potent ENR inhibitors for the future development of medicine

Noncommutative Topological Theories of Gravity

The possibility of noncommutative topological gravity arising in the same manner as Yang-Mills theory is explored. We use the Seiberg-Witten map to construct such a theory based on a SL(2,C) complex connection, from which the Euler characteristic and the signature invariant are obtained. This gives us a way towards the description of noncommutative gravitational instantons as well as noncommutative local gravitational anomalies.Comment: 17+1 pages, LaTeX, no figures, some clarifications, comments and references added, style improve

Dirac's Observables for the Rest-Frame Instant Form of Tetrad Gravity in a Completely Fixed 3-Orthogonal Gauge

We define the {\it rest-frame instant form} of tetrad gravity restricted to Christodoulou-Klainermann spacetimes. After a study of the Hamiltonian group of gauge transformations generated by the 14 first class constraints of the theory, we define and solve the multitemporal equations associated with the rotation and space diffeomorphism constraints, finding how the cotriads and their momenta depend on the corresponding gauge variables. This allows to find quasi-Shanmugadhasan canonical transformation to the class of 3-orthogonal gauges and to find the Dirac observables for superspace in these gauges. The construction of the explicit form of the transformation and of the solution of the rotation and supermomentum constraints is reduced to solve a system of elliptic linear and quasi-linear partial differential equations. We then show that the superhamiltonian constraint becomes the Lichnerowicz equation for the conformal factor of the 3-metric and that the last gauge variable is the momentum conjugated to the conformal factor. The gauge transformations generated by the superhamiltonian constraint perform the transitions among the allowed foliations of spacetime, so that the theory is independent from its 3+1 splittings. In the special 3-orthogonal gauge defined by the vanishing of the conformal factor momentum we determine the final Dirac observables for the gravitational field even if we are not able to solve the Lichnerowicz equation. The final Hamiltonian is the weak ADM energy restricted to this completely fixed gauge.Comment: RevTeX file, 141 page

The single-track reporting approach: The development of finacial and prudential reporting requirements and their impact on the reporting practices of Dutch insurance companies in the period 1880-2005

Camfferman, C. [Promotor]Hoogendoorn RA, M.N. [Copromotor

Differential microRNA expression in cultured palatal fibroblasts from infants with cleft palate and controls

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Metal Mesh Scaffold for Tissue Engineering of Membranes

Engineering of the membrane-like tissue structures to be utilized in highly dynamic loading environments such as the cardiovascular system has been a challenge in the past decade. Scaffolds are critical components of the engineered tissue membranes and allow them being formed in vitro and remain secure in vivo when implanted in the body. Several approaches have been taken to develop scaffolds for tissue membranes. However, all methods entail limitations due to structural vulnerability, short-term functionality, and mechanical properties of the resulted membrane constructs. To overcome these issues, we have developed a novel hybrid scaffold made of an extra thin layer of metal mesh tightly enclosed by biological matrix components. This approach retains all the advantages of using biological scaffolds while developing a strong extracellular matrix that can stand various types of loads after implantation inside the body

Association of Lower Extremity Lymphedema With Physical Functioning and Activities of Daily Living Among Older Survivors of Colorectal, Endometrial, and Ovarian Cancer

Importance: Lower extremity lymphedema (LEL) is associated with decreased physical functioning (PF) and activities of daily living (ADLs) limitations. However, the prevalence of LEL in older survivors of cancer is unknown. Objectives: To examine LEL among older female survivors of colorectal, endometrial, or ovarian cancer and investigate the association of LEL with PF and ADLs. Design, Setting, and Participants: This secondary analysis of the Women's Health Initiative (WHI) Life and Longevity After Cancer (LILAC) study was conducted using data from postmenopausal women enrolled at 40 US centers. Participants were women who had a prior diagnosis of endometrial, colorectal, or ovarian cancer and who had completed the WHI LILAC baseline and year 1 follow-up questionnaires as of September 2017. Exposures: The 13-item Lower Extremity Lymphedema Screening Questionnaire in Women was used to determine LEL (ie, score ≥5). Main Outcomes and Measures: Validated surveys were used to assess PF and ADLs. Results: Among 900 older women diagnosed with endometrial, colorectal, or ovarian cancer, the mean (SD) age was 78.5 (5.9) years and the mean (range) time since cancer diagnosis was 8.75 (1.42-20.23) years. Overall, 292 women (32.4%) reported LEL, with the highest LEL prevalence among survivors of ovarian cancer (38 of 104 women [36.5%]), followed by survivors of endometrial cancer (122 of 375 women [32.5%]) and colorectal cancer (132 of 421 women [31.4%]). Compared with women without LEL, women with LEL had a PF score that was lower by a mean (SE) 16.8 (1.7) points (P < .001) and higher odds of needing help with ADLs (odds ratio [OR], 2.45; 95% CI, 1.64-3.67). In the association of LEL with PF, the mean (SE) decrease in PF score was greatest among survivors of colorectal cancer (-21.8 [2.6]) compared with survivors of endometrial cancer (-13.3 [2.7]) and ovarian cancer (-12.8 [5.2]). Additionally, among survivors of colorectal cancer, LEL was associated with increased odds of needing help with ADLs (OR, 3.59; 95% CI, 1.94-6.66), while there was no such association among survivors of endometrial cancer or ovarian cancer. However, there were no interaction associations between LEL and cancer type for either outcome. Additionally, the overall mean (SE) difference in PF between women with and without LEL was greater among those aged 80 years and older (-19.4 [2.6] points) vs those aged 65 to 79 years (-14.9 [2.2] points). However, among survivors of colorectal cancer, the mean (SE) difference in PF score was greater among women aged 65 to 79 years (-22.9 [3.7] points) vs those aged 80 years or older (-20.8 [3.7] points) (P for 3-way interaction = .03). Conclusions and Relevance: This study found that nearly one-third of older female survivors of colorectal, endometrial, or ovarian cancer experienced LEL and that LEL was associated with decreased PF and increased odds of needing help with ADLs. These findings suggest that clinicians may need to regularly assess LEL among older survivors of cancer and provide effective interventions to reduce LEL symptoms and improve PF for this population.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]