Enhanced near infrared optical access to the brain with a transparent cranial implant and scalp optical clearing.

We report on the enhanced optical transmittance in the NIR wavelength range (900 to 2400 nm) offered by a transparent Yttria-stabilized zirconia (YSZ) implant coupled with optical clearing agents (OCAs). The enhancement in optical access to the brain is evaluated upon comparing ex-vivo transmittance measurements of mice native skull and the YSZ cranial implant with scalp and OCAs. An increase in transmittance of up to 50% and attenuation lengths of up to 2.4 mm (i.e., a five-fold increase in light penetration) are obtained with the YSZ implant and the OCAs. The use of this ceramic implant and the biocompatible optical clearing agents offer attractive features for NIR optical techniques for brain theranostics

Phase Change Material Systems for High Temperature Heat Storage

Efficient, cost effective, and stable high-temperature heat storage material systems are important in applications such as high-temperature industrial processes (metal processing, cement and glass manufacturing, etc.), or electricity storage using advanced adiabatic compressed air energy storage. Incorporating phase change media into heat storage systems provides an advantage of storing and releasing heat at nearly constant temperature, allowing steady and optimized operation of the downstream processes. The choice of, and compatibility of materials and encapsulation for the phase change section is crucial, as these must guarantee good and stable performance and long lifetime at low cost. Detailed knowledge of the material properties and stability, and the coupled heat transfer, phase change, and fluid flow are required to allow for performance and lifetime predictions. We present coupled experimental-numerical techniques allowing prediction of the long-term performance of a phase change material-based high-temperature heat storage system. The experimental investigations focus on determination of material properties (melting temperature, heat of fusion, etc.) and phase change material and encapsulation interaction (stability, interface reactions, etc.). The computational investigations focus on an understanding of the multi-mode heat transfer, fluid flow, and phase change processes in order to design the material system for enhanced performance. The importance of both the experimental and numerical approaches is highlighted and we give an example of how both approaches can be complementarily used for the investigation of long-term performance

The effective potential, critical point scaling and the renormalization group

The desirability of evaluating the effective potential in field theories near a phase transition has been recognized in a number of different areas. We show that recent Monte Carlo simulations for the probability distribution for the order parameter in an equilibrium Ising system, when combined with low-order renormalization group results for an ordinary $\phi^4$ system, can be used to extract the effective potential. All scaling features are included in the process.Comment: REVTEX file, 22 pages, three figures, submitted to Phys. Rev.

Applicability of dynamic facilitation theory to binary hard disk systems

We numerically investigate the applicability of dynamic facilitation (DF) theory for glass-forming binary hard disk systems where supercompression is controlled by pressure. By using novel efficient algorithms for hard disks, we are able to generate equilibrium supercompressed states in an additive nonequimolar binary mixture, where microcrystallization and size segregation do not emerge at high average packing fractions. Above an onset pressure where collective heterogeneous relaxation sets in, we find that relaxation times are well described by a “parabolic law” with pressure. We identify excitations, or soft spots, that give rise to structural relaxation and find that they are spatially localized, their average concentration decays exponentially with pressure, and their associated energy scale is logarithmic in the excitation size. These observations are consistent with the predictions of DF generalized to systems controlled by pressure rather than temperature

Predator telemetry informs temporal and spatial overlap with stocked salmonids in Lake Huron

Double-Crested Cormorants (Phalacrocorax auratus), Walleyes (Sander vitreus), and Lake Trout (Salvelinus namaycush) are migratory predators that undergo extensive movements in Lake Huron. Stocking of juvenile salmonid fish (Oncorhynchus and Salmo sp.) is an important component of fishery management in Lake Huron and assessing the spatial and temporal extent of predator movements is a useful consideration for determining when and where to stock juvenile fish to reduce predation and maximize survival. Previous investigation indicated that some Walleyes migrate to the main basin of Lake Huron in spring from Saginaw Bay. Similarly, telemetry studies of Lake Trout movement in Lake Huron have indicated an onshore movement in the spring. We used detection histories of Walleyes implanted with acoustic transmitters tagged in Saginaw Bay and Lake Trout implanted in northern Lake Huron to estimate the arrival date of migrating adults at eight ports in Lake Huron, where hatchery reared juvenile salmonids are stocked. Satellite telemetry of Cormorants that return to nesting grounds in northern Lake Huron were used to estimate their arrival dates at the same Lake Huron ports. Arrival of Walleye at Lake Huron ports ranged from April 10th to May 7th. Cormorants arrived earlier than Walleye at most Lake Huron ports (April 11th–April 18th). Lake Trout were more variable with a range of onshore movement from March 28th to May 16th. Our results suggested stocking efforts at these ports should generally occur before April 14th to decrease predatory impact from Cormorants, Walleyes, and Lake Trout

Monte Carlo Methods for Estimating Interfacial Free Energies and Line Tensions

Excess contributions to the free energy due to interfaces occur for many problems encountered in the statistical physics of condensed matter when coexistence between different phases is possible (e.g. wetting phenomena, nucleation, crystal growth, etc.). This article reviews two methods to estimate both interfacial free energies and line tensions by Monte Carlo simulations of simple models, (e.g. the Ising model, a symmetrical binary Lennard-Jones fluid exhibiting a miscibility gap, and a simple Lennard-Jones fluid). One method is based on thermodynamic integration. This method is useful to study flat and inclined interfaces for Ising lattices, allowing also the estimation of line tensions of three-phase contact lines, when the interfaces meet walls (where "surface fields" may act). A generalization to off-lattice systems is described as well. The second method is based on the sampling of the order parameter distribution of the system throughout the two-phase coexistence region of the model. Both the interface free energies of flat interfaces and of (spherical or cylindrical) droplets (or bubbles) can be estimated, including also systems with walls, where sphere-cap shaped wall-attached droplets occur. The curvature-dependence of the interfacial free energy is discussed, and estimates for the line tensions are compared to results from the thermodynamic integration method. Basic limitations of all these methods are critically discussed, and an outlook on other approaches is given

The Effect of Ordered Water on a Short, Strong (Speakman-Hadži) Hydrogen Bond

We have determined the structures of the sodium, tetrabutylam- monium (TBA) and bis(triphenylphosphoranylidene)ammonium (PNP) salts of the bis(4-nitrophenoxide) anion by X-ray crystallography. The sodium salt is a dihydrate, with the water oxygens coordinated to the sodium cations, and one hydogen from each water hydrogen bonded to one of the bridging oxygens of the anion. The TBA and PNP salts are anhydrous. Nevertheless the oxygen- oxygen distance is shortest in the sodium salt; 246.5 pm in the sodium salt, 247.5 pm in the TBA salt, and 249 pm in the PNP salt; suggesting that the hydrogen bond is not weakened by the water, and may be strongest in the hydrated salt. (All three compounds show Hadži type ii IR spectra, and are called Speakman-Hadži compounds in this paper.) The 2H chemical shifts of the bridging hydrogen in the three solids are 16.8 ppm for the sodium salt, 16.8 ppm for the TBA salt, and 16.5 ppm for the PNP salt. Again there is no evidence that the water weakens the hydrogen bond. These results can be understood by noting that the additional hydrogen bonds to the bridging oxygens decrease their proton affinity, but the mutual repulsion of the oxygens is also decreased

Adult Comorbidity Evaluation 27 score as a predictor of survival in endometrial cancer patients

BACKGROUND The incidence of endometrial cancer increases with age and is associated with medical comorbidities such as obesity and diabetes. While a few cohort studies of less than 500 patients showed an association between comorbidity and survival in endometrial cancer patients, the degree of association needs to be better described. The Adult Comorbidity Evaluation 27 (ACE-27) is a validated comorbidity instrument that provides a score (0–3) based on the number and severity of medical comorbidities. OBJECTIVE This study was performed to explore the association between medical comorbidities and survival of endometrial cancer patients. STUDY DESIGN Patients diagnosed with endometrial cancer from 2000–2012 were identified from the prospectively maintained Siteman Cancer Center tumor registry. Patients undergoing primary surgical treatment for endometrioid, serous and clear cell endometrial carcinoma were included. Patients primarily treated with radiation, chemotherapy or hormone therapy were excluded. Patients with uterine sarcomas or neuroendocrine tumors were excluded. Patients with missing ACE-27 scores were also excluded from analysis. Information including patient demographics, ACE-27 score, tumor characteristics, adjuvant treatment and survival data were extracted from the database. The association of ACE-27 and overall as well as recurrence-free survival was explored in a multivariable Cox regression analysis after controlling for variables found to be significantly associated with survival in univariable analysis. RESULTS A total of 2073 patients with a median age of 61 years (range 20–94) at diagnosis were identified. ACE-27 score was 0, 1, 2 and 3 in 22%, 38%, 28% and 12% of patients, respectively. Stage distribution was I (73%), II (5%), III (15%) and IV (7%) and grade distribution was 1 (52%), 2 (23%) and 3 (25%). Most patients had endometrioid histology (87%) followed by serous (11%) and clear cell (3%). The median OS for the entire cohort was 54 months [95% confidence interval (CI) 3, 154 months] and median PFS was 50 months [95% CI 2, 154 months]., On univariable analysis, age, race, marital status, stage, grade, histology and treatment type were significantly associated with overall survival and recurrence-free survival. After adjusting for these covariates, patients with ACE-27 score of 2 had a 52% higher risk of death [95% CI 1.16, 2.00] and patients with ACE-27 score of 3 had a 2.35-fold increased risk of death [95% CI 1.73, 3.21] compared to patients with an ACE-27 score of 0. Similarly, patients with ACE-27 score of 2 had a 38% higher risk of recurrence [95% CI 1.07, 1.78] and patients with ACE-27 score of 3 had a 2.05-fold increased risk of recurrence [95% CI 1.53, 2.75] compared to patients with an ACE-27 score of 0. We found no interaction between ACE-27 score and age, stage or treatment type. CONCLUSIONS Our findings demonstrate the importance of comorbidities in estimating the prognosis of endometrial cancer patients, even after adjusting for age and known tumor-specific prognostic factors like stage, grade, histology and adjuvant treatment

The Relevance of the Colon to Zinc Nutrition

Globally, zinc deficiency is widespread, despite decades of research highlighting its negative effects on health, and in particular upon child health in low-income countries. Apart from inadequate dietary intake of bioavailable zinc, other significant contributors to zinc deficiency include the excessive intestinal loss of endogenously secreted zinc and impairment in small intestinal absorptive function. Such changes are likely to occur in children suffering from environmental (or tropical) enteropathy (EE)—an almost universal condition among inhabitants of developing countries characterized by morphologic and functional changes in the small intestine. Changes to the proximal gut in environmental enteropathy will likely influence the nature and amount of zinc delivered into the large intestine. Consequently, we reviewed the current literature to determine if colonic absorption of endogenous or exogenous (dietary) zinc could contribute to overall zinc nutriture. Whilst we found evidence that significant zinc absorption occurs in the rodent colon, and is favoured when microbially-fermentable carbohydrates (specifically resistant starch) are consumed, it is unclear whether this process occur in humans and/or to what degree. Constraints in study design in the few available studies may well have masked a possible colonic contribution to zinc nutrition. Furthermore these few available human studies have failed to include the actual target population that would benefit, namely infants affected by EE where zinc delivery to the colon may be increased and who are also at risk of zinc deficiency. In conducting this review we have not been able to confirm a colonic contribution to zinc absorption in humans. However, given the observations in rodents and that feeding resistant starch to children is feasible, definitive studies utilising the dual stable isotope method in children with EE should be undertaken.G.L. Gopalsamy, D.H Alpers, H.J Binder, C.D. Tran, B.S. Ramakrishna, I. Brown, M. Manary, Elissa Mortimer and G.P. Youn

Phase transition of meshwork models for spherical membranes

We have studied two types of meshwork models by using the canonical Monte Carlo simulation technique. The first meshwork model has elastic junctions, which are composed of vertices, bonds, and triangles, while the second model has rigid junctions, which are hexagonal (or pentagonal) rigid plates. Two-dimensional elasticity is assumed only at the elastic junctions in the first model, and no two-dimensional bending elasticity is assumed in the second model. Both of the meshworks are of spherical topology. We find that both models undergo a first-order collapsing transition between the smooth spherical phase and the collapsed phase. The Hausdorff dimension of the smooth phase is H\simeq 2 in both models as expected. It is also found that H\simeq 2 in the collapsed phase of the second model, and that H is relatively larger than 2 in the collapsed phase of the first model, but it remains in the physical bound, i.e., H<3. Moreover, the first model undergoes a discontinuous surface fluctuation transition at the same transition point as that of the collapsing transition, while the second model undergoes a continuous transition of surface fluctuation. This indicates that the phase structure of the meshwork model is weakly dependent on the elasticity at the junctions.Comment: 21 pages, 12 figure