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Nutrition is a significant determinant in the leading causes of death in the USA, and yet recent studies have shown that most American medical schools provide insufficient nutrition education. To address this deficiency, a concise and updated set of nutrition learning objectives was created from the 2002 Nutrition Curricular Guide for Training Physicians. A panel of 66 experts provided feedback to revise the initial objectives. The resulting objectives are presented here, as well as one recommended overarching goal to help match the needs of patients with the skills of future physicians.

We demonstrate that ferroelectric (FE) polarizations oriented along the finite thickness direction in ultrathin films are enhanced by the introduction of extreme curvature, thereby suppressing the finite-size-driven evolution of the FE phase transition temperature T(C). The measured responses within individual nanoshells possess magnitudes nearly three times that for their planar counterparts while exhibiting finite curvature-dependent offsets in FE switching hystereses. In stark contrast to the expected scaling of a depression of T(C) with inverse thickness, results based on modified Landau-Ginzburg model calculations indicate geometric curvature-driven polarization gradients in ultrathin films result in significant increases in T(C).

Using a synchrotron X-ray radiation source and a diamond anvil cell we measured the dependences of the lattice parameters on quasi-hydrostatic pressure of the order of 50 GPa of the following MAX phases: Ti2InC, (Ti0.5,Zr0.5)2InC, Zr2InC and Ti2SnC, Nb2InC and Hf2InC. Like other MAX phases, the phases studied herein were all stable up to ≈50 GPa. In both series, the substitution of Ti ( r = 1.32 A ) by the larger sized metals, Zr or Nb (with r varying between 1.34 and 1.55 A) resulted in larger unit cell parameters and volumes. At 152±3 and 148±3 GPa, the respective bulk moduli, K o , of Ti2SnC and Ti2InC are quite comparable. Replacing Ti by Hf or Nb in Ti2SnC leads to increases in K o by 11% and 18%, respectively. Conversely, replacing half the Ti by Zr in Ti2InC leads to a 13% drop in K o ; replacing all of the Ti drops it by 16.5%. Most of these trends are reproduced in our ab initio calculations of K o . For all compositions, the compressibilities along the c -direction were greater than those along the a -direction. For the M2SnC series, the compressibilities along the c -axes were quite similar; the compressibilities along the a -axis of Ti2SnC were greater than in the Nb- or Hf-containing ternaries. The c -axis compressibilities of the In-containing compounds were almost indistinguishable. The compressibilities along the a -axes of (Ti0.5,Zr0.5)2InC and Zr2InC were also quite comparable; those of Ti2InC was less compressible.

We report on the one-phonon Raman scattering spectra from the following M2AC MAX-phase ternary carbides: Ti2AlC, V2AlC, Cr2AlC, Nb2AlC, Ta2AlC, Ti2InC, Hf2InC, V2GeC, Cr2GeC, V2AsC, and Nb2AsC. We also report the results of calculations of the Γ-point, Raman-active phonon energies for these phases based on density functional theoretical simulations, including the effect of the k-point sampling on the convergence of phonon energies. Good agreement between all measured and calculated Γ-point Raman-active optical phonon energies is obtained.

A mechanism of the rearrangement of 5-propargyloxyindoles is proposed and supported by the formation of a novel tetracyclic indole derivative 12 as the major product in the cyclization of 5-propargyloxytryptophol 10 .

A mechanism of the rearrangement of 5-propargyloxyindoles is proposed and supported by the formation of a novel tetracyclic indole derivative 12 as the major product in the cyclization of 5-propargyloxytryptophol 10 .

The Greta oto, or the “glasswing butterfly”, is a member of the Ithomiini tribe. Although rare among lepidopteran, the G. oto’s wings are naturally transparent. To understand the material properties of natural transparency, the various structures on the surface of the wings, both the transparent and brown “veins” and wing parameter regions were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), reflectance spectrometry, transmission spectrometry and scanning probe microscopy (SPM) in order to investigate their local structure, periodic character, and electromechanical response. Nanosized protuberances in a highly ordered array were found on the surface of the transparent part similar to that of the “corneal nipple array” found in other insects as an antireflective device.

Two hundred forty-eight patients were operated for perforated peptic ulcer between 1983 and 1998. Of the patients 112 (45.1%) had chronic, 34 (13.7%) had acute ulcer history and 102 (41.2%) had no ulcer history. Of the patients 228 (92.0%) had duodenal, 9 (3.6%) had juxtapyloric, 6 (2.4%) had marginal, and 5 (2.0%) had antral ulcer. Forty two patients (16.9%) admitted within 12 hours and 206 patients (83.1%) between 12 hours and six days after perforation. Simple closure and omental patch was performed in 32 patients (12.9%) who had severe concomitant illness and 126 (50.8%) intraabdominal sepsis, truncal vagotomy + pyloroplasty in 32 (12.9%), simple closure + omental patch + truncal vagotomy + gastroenterostomy in 34 (13.7%), simple closure + omental patch + parietal cell vagotomy in 21 (8.5%), truncal vagotomy + antrectomy in 3 (1.2%). Patients who didn't have definitive procedure received H2 receptor blockers or proton pomp inhibitors. One hundred ninety-three patients (77.8%) underwent endoscopic control. Two of 53 patients with definitive procedure (3.8%) and 34 of 140 patients (24.3%) with simple closure had recurrence. Two patients in simple closure group underwent parietal cell vagotomy, the others received medical treatment. The recurrence rate was significantly higher in simple closure group (p0.01).

Nanowires each consisting of a magnetostrictive Co core and a PbZr0.52Ti0.48O3 or BiFeO3 ferroelectric oxide shell exhibit a magnetic field-tunable piezoelectric response and ferroelectric coercivity owing to magneto-elastic coupling through the interfacial core-shell boundary. The observed magneto-elastic tuning of the ferroelectric switching is analyzed using a renormalized Landau-Ginzburg stiffness in which a magnetic field-tunable stress concentration is incorporated. These results provide insight into the design of integrated functional devices and magnetoelectric sensors.

Herein we report on a systematic investigation of the thermal expansion of select Mn+1AXn phases. The bulk dilatometric thermal expansion coefficient αdil was measured in the 25–1200 °C temperature range and the thermal expansion of more than 15 of these phases was studied by x-ray diffraction in the 25–800 °C temperature range. The coefficient of thermal expansion for the a axis αa ranged between (2.9±0.1)×10−6 °C−1 (Nb2AsC) and (12.9±0.1)×10−6 °C−1 (Cr2GeC) while the coefficient for the c axis (αc) ranged between (6.4±0.2)×10−6 °C−1 (Ta2AlC) and (17.6±0.2)×10−6 °C−1 (Cr2GeC). Weak anisotropy in the thermal expansion was seen in most phases, with the largest value of αc/αa belonging to Nb2AsC. The Gruneisen parameters along the a and c directions were calculated from ab initio values for the elastic compliances and were relatively isotropic. A good correlation was found between the thermal expansion anisotropy and the elastic constant c13 and we conclude that the anisotropy in thermal expansion is relate...

We report on the electronic, thermal, and elastic properties of the layered ternary, Ti2SC. Resistivity, Hall effect, and magnetoresistance were measured as a function of temperature between 2 and 300 K and at fields up to 9 T. The Hall coefficient is negative and roughly temperature independent. The transport results were analyzed within a two-band framework, with electrons as the dominant charge carrier. The room-temperature thermal conductivity (≈60 W/m K) is the highest of any MAX phase measured to date, with a substantial phonon contribution. The specific heat was measured from 2 to 300 K, yielding a Debye temperature of 765 K and in agreement with the Debye temperature of 745 K found from ultrasonic time-of-flight measurements. Young’s, shear, and bulk moduli from the latter measurements were 290, 125, and 145 GPa, respectively. The calculated values of the lattice parameters (a=3.2051 A and c=11.2636 A), and Young’s, shear, and bulk moduli (329, 138, and 179 GPa, respectively), based on the results...

Herein we report on the heat capacities cp of bulk predominantly single-phase polycrystalline samples of Ti2SC and Cr2GeC in the 3–1500K temperature range and Ta2AlC in the 3–260K range. At temperatures up to 10K the main contributors to cp for Ta2AlC and Cr2GeC are electronic, with electronic coefficients γ of 7.13 and 26.12mJ∕molK2, respectively. The latter is exceptionally high and is a record for this family of layered ternary carbides and nitrides also known as the MAX phases. In Ti2SC another low-temperature contribution—in addition to a γ of 3.8mJ∕molK2—is manifested by an upturn in cp∕T observed at the lowest temperatures. This feature, appearing as a Schottky-like anomaly, has a local maximum near 4.5K and an intensity of ∼1.9×10−2J∕molK. A defect concentration of ∼3×1021∕mol presumably on the S-sublattice, is proposed as the origin of a two-level energy system responsible for this anomaly. As in previous work on these compounds, the lattice contributions to cp in all compounds are analyzed using...

Reproductive characteristics of three sympatric species of Gentiana exhibiting perennial and non-perennial life histories were studied in alpine meadows of the White Mountains of California during three consecutive years. High fruit and seed set and the production of a relatively large number of seeds characterized the alpine biennials, Gentiana tenella and G. prostrata. In contrast, fruit and seed set were considerably reduced and yearly seed production was relatively low in the alpine perennial, G. newberryi. Successful seed production in the biennial species was a result of low rates of flower predation, self-pollination, and the allocation of a comparatively high proportion of biomass to reproductive structures. Seed production in the perennial species was limited by high rates of flower predation, insufficient amounts of pollen reaching stigmas, an unusually late flowering period, and by the relatively small proportion of biomass allocated to reproduction.