Hydrology and climatology at Laguna La Gaiba, lowland Bolivia: complex responses to climatic forcings over the last 25,000 years

Diatom, geochemical and isotopic data provide a record of environmental change in Laguna La Gaiba, lowland Bolivia, over the last ca. 25 000 years. High-resolution diatom analysis around the last glacial–interglacial transition provides new insights into this period of change. The full and late glacial lake was generally quite shallow, but with evidence of periodic flooding. At about 13,100 cal a BP, just before the start of the Younger Dryas chronozone, the diatoms indicate shallower water conditions, but there is a marked change at about 12,200 cal a BP indicating the onset of a period of high variability, with rising water levels punctuated by periodic drying. From ca. 11,800 to 10,000 cal a BP stable, deeper water conditions persisted. There is evidence for drying in the early to middle Holocene, but not as pronounced as that reported from elsewhere in the southern hemisphere tropics of South America. This was followed by the onset of wetter conditions in the late Holocene consistent with insolation forcing. Conditions very similar to present were established about 2,100 cal a BP. A complex response to both insolation forcing and millennial scale events originating in the North Atlantic is noted

the Dedication of the New Chemistry Building, University of Illinois

The new Chemistry Building of the University of Illinois was formally dedicated on the 19th of April (1916). The exercises were held in the Auditorium. Document includes the program and speeches.Ope

From thermal rectifiers to thermoelectric devices

We discuss thermal rectification and thermoelectric energy conversion from the perspective of nonequilibrium statistical mechanics and dynamical systems theory. After preliminary considerations on the dynamical foundations of the phenomenological Fourier law in classical and quantum mechanics, we illustrate ways to control the phononic heat flow and design thermal diodes. Finally, we consider the coupled transport of heat and charge and discuss several general mechanisms for optimizing the figure of merit of thermoelectric efficiency.Comment: 42 pages, 22 figures, review paper, to appear in the Springer Lecture Notes in Physics volume "Thermal transport in low dimensions: from statistical physics to nanoscale heat transfer" (S. Lepri ed.

Measurements of the γvp→p′π+π- cross section with the CLAS detector for 0.4 GeV2<Q2<1.0 GeV2 and 1.3 GeV<W<1.825 GeV

New results on the single-differential and fully integrated cross sections for the process γvp→p′π+π- are presented. The experimental data were collected with the CLAS detector at Jefferson Laboratory. Measurements were carried out in the kinematic region of the reaction invariant mass W from 1.3 to 1.825 GeV and the photon virtuality Q2 from 0.4 to 1.0 GeV2. The cross sections were obtained in narrow Q2 bins (0.05 GeV2) with the smallest statistical uncertainties achieved in double-pion electroproduction experiments to date. The results were found to be in agreement with previously available data where they overlap. A preliminary interpretation of the extracted cross sections, which was based on a phenomenological meson-baryon reaction model, revealed substantial relative contributions from nucleon resonances. The data offer promising prospects to improve knowledge on the Q2 evolution of the electrocouplings of most resonances with masses up to ∼1.8 GeV

Potential risk of monochorionic dizygotic twin blastocyst formation associated with early laser zona dissection of group cultured embryos

Objective: To document the risk of in vitro monochorionic dizygotic twin formation in the implementation of a program of blastocyst biopsy with preimplantation genetic screening (PGS). Design: Case report. Setting: Private infertility laboratory. Patient(s): Prospective PGS patients with intracytoplasmic sperm injection-derived, group-cultured blastocysts over a 3-year period. Intervention(s): Group culture in Global medium (Life Global) to optimize blastocyst formation of zygotes produced for blastocyst biopsy for PGS (n % 8 embryos/25 mL droplet), and laser zona dissection (LZD) of all day-3 cleaved embryos to promote preexpansion trophectodermal extrusion at the blastocyst stage (i.e., premature hatching). Main Outcome Measure(s): Blastocyst formation and quality grading on days 5 and 6 of in vitro culture for the vitrified embryo transfer of single or dual euploid blastocysts. Result(s): Over 3,000 blastocysts were produced in vitro. On two separate occasions, complete trophectodermal amalgamation was observed between two hatching blastocysts. Vitrified single-euploid blastocyst transfers efficiently implanted and established clinical pregnancies similar to dual-euploid blastocyst transfers, without the risk of twin formation. Conclusion(s): The amazing occurrence of monochorionic dizygotic twin formation has now been documented in vitro, supporting the theory that assisted reproductive technology may facilitate this rare perinatal condition. Furthermore, we have provided clinical evidence that the transfer of a single-euploid blastocyst can optimize a patient&apos;s pregnancy success while reducing potentially undesirable conditions associated with monochorionic twin pregnancies. (Fertil Steril Ò 2015;103:417-21. Ó2015 by American Society for Reproductive Medicine.) Key Words: Blastocysts, in vitro derived, monochorionic dizygotic twins Discuss: You can discuss this article with its authors and with other ASRM members at http:// fertstertforum.com/schiewem-monochorionic-dizygotic-twin-early-lzd

Platelet-Rich Plasma Augmentation for Hip Arthroscopy

Biological augmentation and therapeutics are being increasingly used in musculoskeletal and orthopaedic care. Platelet-rich plasma (PRP) is produced from centrifugation of peripheral blood, a process that concentrates platelets within autologous plasma. The process of PRP preparation is fundamental in controlling the contents, and it influences its therapeutic potential. Platelets contain alpha granules that store and release a variety of growth factors and other proteins that may augment the healing environment; PRP also has the added benefit of promoting postsurgical hemostasis. The purpose of this report was to detail our institutional preparation protocol and method of administration of PRP during hip arthroscopy