bluuebunny/crossref_metadata_2025 huggingface dataset:
Semi‐automatic profiling from SEM stereopairs
Authors: Howell P. G. T.
Published: October 2011

Modifications were made to a stereometer to permit semi‐automatic profiling from SEM stereopair micrographs. The design was based upon a mirror stereoscope with a parallax measuring facility, to which was added a linear transducer to monitor the parallax readings and an X‐Y digitising tablet to provide (x, y) coordinate values of specific features. Transmission to a mini computer of these digitised coordinates and parallax was triggered by a microswitch allowing the operator to maintain his attention on the measurements from the stereometer. The computer calculated the “Z” coordinates which could then be output graphically to its visual display unit or to a plotter/printer for hard copy results.

This system permits the rapid accumulation of data from the stereopair micrographs while

reducing operator fatigue, due to the elimination of manual recording of data values between individual measurements, and

improving the accuracy of the results required, since errors due to misreading or misrecording data are eliminated.
Application of backscattered electron images to the study of fracture in glass ceramics
Authors: Healey J. T. , Mecholsky J. J.
Published: October 2011

Fracture surfaces of three different glass ceramics were examined to determine the critical flaw sizes and the corresponding microstructures of the materials directly from the fracture surfaces. Standard secondary electron (SE) images and classical topographical back‐scattered electron (BSE) images were used to measure the critical flaw sizes and to observe deviations of the critical flaw interfaces from smooth elliptical fronts. Compositional BSE images were used to characterize the microstructures in and around the critical flaws directly from the unetched fracture surfaces.

A direct correlation was found between the critical flaw size and microstructural units effectively acting as grains within the flaw and the fracture toughness. This relationship enabled the discrepancies between the calculated fracture toughness and the measured fracture toughness to be resolved.
Design and use of a computer controlled confocal microscope for biological applications
Authors: van der Voort H. T. M. , Brakenhoff G. J. , Valkenburg J. A. C. , Nanninga N.
Published: October 2011

In the confocal scanning light microscope where the object is scanned mechanically through a finely focused laser spot, a fundamentally higher resolution can be achieved when a point detector is employed. Such a microscope possesses in addition to a high dynamic range excellent sectioning capabilities, and is because of this very suitable for “3‐Dimensional imaging”, especially when operated in fluorescence. An instrument under computer control and with extensive image processing capabilities is described. Various biological applications are given including computer generated stereo images of biological structures with submicron resolution.
Combining the microcomputer with electron optical devices—A way to realize new image forming systems
Authors: Erdmann M. , Hylla W. , Niedrig H.
Published: October 2011

This contribution deals with the use of microprocessors adapted to electron optical devices, to get new and unconventional image‐forming systems. Examples of four specific investigations are shown. In the first part, the dependence of the diffraction contrast in convergent beam patterns on the energy loss of the collected electrons has been investigated. In the second part, an arrangement for sensitive film thickness measurements with high lateral resolution has been applied to record ejection patterns of single crystals under ion bombardment. A method for the calculation of thickness level charts on the microcomputer is explained.
Noise reduction in high‐magnification micrographs by soft focus printing and digital image processing
Authors: Peters Klaus‐Ruediger
Published: October 2011

Soft focus printing of micrographs, using screens of opaque material with 10–15 lines/cm, reduced contrast due to noise but preserved all other contrasts and all structural details. Appropriate screens generated diffraction fringes of a spacing similar to the distance of the noise structures. The superimposition of fringes and image produced a diffusion effect which reduced only the contrast of the noise background. Blurring, screening or fogging were not effective or suitable for photographic micrograph processing. Soft focus printing improved recognition of weak high magnification contrasts in SEM micrographs of uncoated, gold decorated, and chromium coated cell surfaces of glomerular endothelium in mouse kidney slices. Effects similar to the optical diffusion were obtained by digital image processing using weighted low pass filters.
Effects of di(2‐ethylhexyl)phthalate on testicular oxidant/antioxidant status in selenium‐deficient and selenium‐supplemented rats
Authors: Erkekoglu Pınar , Giray Belma , Rachidi Walid , Hininger‐Favier Isabelle , Roussel Anne‐Marie , Favier Alain , Hincal Filiz
Published: October 2011

Di(ethylhexyl)phthalate (DEHP), the most widely used plasticizer, was investigated to determine whether an oxidative stress process was one of the underlying mechanisms for its testicular toxicity potential. To evaluate the effects of selenium (Se), status on the toxicity of DEHP was further objective of this study, as Se is known to play a critical role in testis and in the modulation of intracellular redox equilibrium. Se deficiency was produced in 3‐weeks‐old Sprague–Dawley rats feeding them ≤0.05 mg Se /kg diet for 5 weeks, and Se‐supplementation group was on 1 mg Se/kg diet. DEHP‐treated groups received 1000 mg/kg dose by gavage during the last 10 days of the feeding period. Activities of antioxidant selenoenzymes [glutathione peroxidase 1 (GPx1), glutathione peroxidase 4 (GPx4), thioredoxin reductase (TrxR)], catalase (CAT), superoxide dismutase (SOD), and glutathione S‐transferase (GST); concentrations of reduced glutathione (GSH), oxidized glutathione (GSSG), and thus the GSH/GSSG redox ratio; and thiobarbituric acid reactive substance (TBARS) levels were measured. DEHP was found to induce oxidative stress in rat testis, as evidenced by significant decrease in GSH/GSSG redox ratio (>10‐fold) and marked increase in TBARS levels, and its effects were more pronounced in Se‐deficient rats with ∼18.5‐fold decrease in GSH/GSSG redox ratio and a significant decrease in GPx4 activity, whereas Se supplementation was protective by providing substantial elevation of redox ratio and reducing the lipid peroxidation. These findings emphasized the critical role of Se as an effective redox regulator and the importance of Se status in protecting testicular tissue from the oxidant stressor activity of DEHP. © 2011 Wiley Periodicals, Inc. Environ Toxicol 29: 98–107, 2014.
Thickness and angular dependence of the L‐edge X‐ray absorption of nickel thin films
Authors: Ufuktepe Y. , Akgül G. , Aksoy F. , Nordlund D.
Published: October 2011

We report on the near‐edge X‐ray absorption fine structure spectroscopy of the L3 (2p3/2) and L2 (2p1/2) edges for ferromagnetic pure nickel transition metal and show that the L2,3 edge peak intensity and satellite feature at ~6 eV above the L3 edge in nickel increase with increasing nickel film thickness both in the total electron yield and transmission modes. The absorption spectra of nickel metal, however, exhibit strong angular‐dependent effects when measured in total electron yield mode. In addition, we calculated the mean electron escape depth of the emitted electrons (λe), which was found for pure nickel metal to be λe=25 ± 2 Å. We point out the advantages of the total electron yield technique for the study of the L‐edge of 3d transition metals. Copyright © 2011 John Wiley & Sons, Ltd.
Characterization of the Metrology beamline at the SOLEIL synchrotron and application to the determination of mass attenuation coefficients of Ag and Sn in the range 3.5 ≤ E ≤ 28 keV
Authors: Ménesguen Y. , Lépy M.‐C.
Published: October 2011

This work presents the new Metrology beamline at the SOLEIL synchrotron facility and a first attempt to quantitative measurements of mass attenuation coefficients for Ag and Sn performed on the hard X‐ray branch. We first describe the beamline itself and the characterization performed of the unfocused monochromatic beam running mode. We performed a first experimental measurement of mass attenuation coefficients in the range 3.5 ≤ E ≤ 28 keV and we also derived the K‐absorption and L‐absorption jump ratios. The results are compared with theoretical values as well as with other experimental data and agree well with previous published values. Copyright © 2011 John Wiley & Sons, Ltd.
Anatomical Variations of Hepatic Veins: Three‐Dimensional Computed Tomography Scans of 200 Subjects
Authors: Fang Chi‐Hua , You Jin‐Hua , Lau Wan Yee , Lai Eric C. H. , Fan Ying‐Fang , Zhong Shi‐Zhen , Li Ke‐Xiao , Chen Zhi‐Xiang , Su Zhong‐He , Bao Su‐Su
Published: October 2011

Background

The impact of hepatic venous anatomic variations on hepatic resection and transplantation is the least understood aspect of liver surgery.

Methods

A prospective three‐dimensional computed tomography study was undertaken on 200 consecutive subjects with normal livers to determine the prevalence of surgically significant hepatic venous anatomic variations.

Results

The prevailing pattern of the three hepatic veins in these subjects was a right hepatic vein (RHV) and a common trunk for the middle (MHV) and left (LHV) hepatic veins (122/200, 61%). The remaining patients had the RHV, MHV, and LHV draining independently into the inferior vena cava (IVC). In 39% of patients, the RHV was small and was compensated by a large right inferior hepatic vein (21.0%), an accessory RHV (8.5%) or a well‐developed MHV (6.5%). A segment 4 vein was seen in 51.5% of patients. This segment 4 vein joined the LHV (26%), the MHV (17.5%), or the IVC (8%). An umbilical vein and a segment 4 vein were seen in 3.5% of patients. These two veins joined either the LHV (2.0%) or the MHV (1.5%).

Conclusions

Knowing the variations of hepatic veins before surgery is useful during both partial hepatectomy and donor operations for living related liver transplantation.
Effect of Perioperative Intensive Insulin Therapy for Liver Dysfunction After Hepatic Resection
Authors: Okabayashi Takehiro , Ichikawa Kengo , Namikawa Tsutomu , Sugimoto Takeki , Kobayashi Michiya , Hanazaki Kazuhiro
Published: October 2011

Background

Intensive insulin therapy (IIT) reduces morbidity and mortality in patients in surgical care units, yet the benefits of IIT during liver surgery, especially on liver function after hepatic resection, are not known. The aim of the present study was to assess the effects of IIT, with a focus on postoperative liver function, in hepatectomized patients.

Methods

A total of 150 patients who underwent surgical management for hepatic diseases between September 2007 and March 2009 at Kochi Medical School were investigated. Patients were divided into two groups: (1) those receiving IIT via a closed‐loop glycemic control system (i.e., an artificial pancreas; AP group; n = 74); or (2) those receiving conventional insulin therapy using the sliding scale method (SS group; n = 76). The targeted blood glucose zones in the AP and SS groups were 80–110 and 150–200 mg/dl, respectively.

Results

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels increased and prothrombin time (%) decreased immediately after surgery in both groups. There was a significant difference in postoperative ALT levels between the two groups on postoperative days 1 and 6. Hepatocyte injury and changes in AST and ALT levels after surgery (compared with preoperative levels) were significantly greater in the SS group than AP group after liver resection. During the first 18 h after hepatic resection, 174 IU of insulin was required per patient for tight glycemic control with IIT.

Conclusions

Perioperative IIT ameliorated liver dysfunction after hepatic resection. Liver regeneration and/or an antiinflammatory effect of IIT may underlie its protective effects against hepatocyte injury in hepatectomized patients.
A Mental Health Needs Assessment of Urban American Indian Youth and Families
Authors: West Amy E. , Williams Ellen , Suzukovich Eli , Strangeman Kathlene , Novins Douglas
Published: October 2011

American Indian (AI) youth experience significant mental health disparities. The majority of AI youth live in urban areas, yet urban AI youth are underserved and unstudied. This manuscript describes a qualitative study of community mental health needs in an urban population of AI youth, conducted as part of the planning process for a system of care (SOC). Participants included 107 urban AI youth and families that participated in one of 16 focus groups assessing mental health needs and services. Forty‐one percent of participants were youth or young adults. Data were coded and analyzed using qualitative software and then further analyzed and interpreted in partnership with a community research workgroup. Results indicated various community characteristics, mental health and wellness needs, and service system needs relevant to developing a system of care in this community. Key community, cultural, and social processes also emerged, reinforcing the importance of broader system changes to promote a sustainable SOC. These systems/policy changes are reviewed in the context of previous literature proposing necessary systems change to support behavioral health care in AI communities as well as to ensure that SOC implementation is consistent with core values and philosophy across all communities.
Performance of extra-early maize cultivars based on GGE biplot and AMMI analysis
Authors: BADU-APRAKU B. , OYEKUNLE M. , OBENG-ANTWI K. , OSUMAN A. S. , ADO S. G. , COULIBAY N. , YALLOU C. G. , ABDULAI M. , BOAKYEWAA G. A. , DIDJEIRA A.
Published: October 2011

Multi-environment trials (METs) in West Africa have demonstrated the existence of genotype×environment interactions (G×E), which complicate the selection of superior cultivars and the best testing sites for identifying superior and stable genotypes. Two powerful statistical tools available for MET analysis are the additive main effects and multiplicative interaction (AMMI) and the genotype main effect+G×E (known as GGE) biplot. The objective of the present study was to compare their effectiveness in identifying maize mega-environments and stable and superior maize cultivars with good adaptation to West Africa. Twelve extra-early maturing maize cultivars were evaluated at 17 locations in four countries in West Africa from 2006 to 2009. The effects of genotype (G), environments (E) and G×E were significant (P<0 01) for grain yield. Differences between E accounted for 0 75 of the total variation in the sum of squares for grain yield, whereas the G effects accounted for 0 03 and G×E for 0 22. The GGE biplot explained 0 74 of total variations in the sum of squares for grain yield and revealed three mega-environments and seven cultivar groups. The AMMI graph explained 0 13 and revealed four groups each of environments and cultivars. The two procedures provided similar results in terms of stability and performance of the cultivars. Both methods identified the cultivars 2004 TZEE-W Pop STR C4 and TZEE-W Pop STR C4 as superior across environments. Cultivar 2004 TZEE-W Pop STR C4 was the most stable. The GGE biplot was more versatile and flexible, and provided a better understanding of G×E than the AMMI graph. It identified Zaria, Ilorin, Ikenne, Ejura, Kita, Babile, Ina and Angaredebou as the core testing sites of the three mega-environments for testing the Regional Uniform Variety Trials-extra-early.
Morphological and molecular evidence placesMaroninainto synonymy withProtoparmelia(Ascomycota:Lecanorales)
Authors: PAPONG K. , KANTVILAS G. , LUMBSCH H. T.
Published: October 2011

The phylogenetic placement of the genusMaroninawas studied, based chiefly on phenotypic characters such as thallus colour and anatomy, secondary chemistry, the anatomy of the excipulum and the ascus-type. DNA sequence data of mitochondrial and nuclear ribosomal loci from some of the species support the hypothesis thatMaroninais nested withinProtoparmelia. Hence,Maroninais reduced to synonymy withProtoparmelia. Comparison of genetic distances suggests that the two varieties withinM. orientalisshould be regarded as distinct species. Consequently, the new combinationsProtoparmelia australiensis(Hafellner & R. W. Rogers) Kantvilaset al., P. corallifera(Kantvilas & Papong) Kantvilaset al.,P. hesperia(Kantvilas & Elix) Kantvilaset al., P. multifera(Nyl.) Kantvilaset al., andP. orientalis(Kantvilas & Papong) Kantvilaset al. are proposed.
The checklist of parmelioid and similar lichens in Europe and some adjacent territories: additions and corrections
Authors: HAWKSWORTH David L. , DIVAKAR Pradeep K. , CRESPO Ana , AHTI Teuvo
Published: October 2011

Additions and corrections to the checklist published in 2008 are presented. Ten additional species are recognized: Allantoparmelia almquistii, Asahinea chrysantha, Hypogymnia bryophila, Hypotrachyna afrorevoluta, Melanelixia glabratula, Parmelia encryptata, Parmelina atricha, P. cryptotiliacea, Parmotrema cinereopruinata, and Punctelia rudecta. Myelochroa subaurulenta is deleted, and Xanthoparmelia perezdepazii is also noted as newly described from the Canary Islands. In addition, Cavernularia hultenii is now placed in Hypogymnia, the Canoparmelia crozalsiana group is included within Parmotrema, and Parmelinopsis is treated as a synonym of Hypotrachyna. The typification of the name Lichen quercinus is also corrected with the designation of the original figure as lectotype, and the new combination Hypotrachyna cryptochlora comb. nov. (syn. Parmelia cryptochlora) is made.
News and social media: Windows into community perspectives on disinvestment
Authors: Street Jackie M. , Hennessy Sophie E. , Watt Amber M. , Hiller Janet E. , Elshaug Adam G.
Published: October 2011

Objectives:The aim of this study, in the context of disinvestment related health technology assessment, is to examine whether analysis of Web 2.0—commercial media output, blogs, and discussion forums—can provide an understanding of media framing, community perspectives, and the sociopolitical aspects of an entrenched technology.

Methods: Thematic analysis of relevant data from fifty-nine media articles, thirty-nine discussion forums, thirteen blogs, and three Facebook pages relating to our case study: public funding for assisted reproductive technology services. Mainstream media and community-based social media responses were compared.

Results:Media responses were narrow, primarily describing emotive individual narratives or the political nexus of interests. Community (including patient) responses were broader including discussion of opportunity cost and vested interests but mostly reflected the polar ends of the debate, diverging strongly for or against disinvestment from public funding.

Conclusion:Web2.0 and media analysis offers an inexpensive method to capture media portrayal, divergent community responses both to that portrayal and independent of it, and insight into the sociopolitical aspects of an entrenched technology undergoing disinvestment debate.
A Godement theorem for locales
Authors: Kock Anders
Published: October 2011

The classical Godement Theorem for manifolds, characterizing kernel pairs for submersions (cf. e.g. [15], LG IV §5), has been used by Pradines[12] as a crucial property for having a good theory of differentiable groupoids; in fact, he developed an axiomatic theory of categories in which Godement's and some other exactness properties hold, under the name of ‘Godement diptych’.
Characterization of inverse-closed Beurling classes
Authors: Siddiqi Jamil A. , Ider Mostefa
Published: October 2011

In [1], J. Bruna studied the Beurling classes EM(I) of infinitely differentiable functions f defined on an interval I such that for every positive ε, there exists a constant Cε > 0 with the property that

where M = {Mn} is a given sequence of positive numbers. With the hypothesis that the class EM(ℝ) is differentiable, he proved that it is inverse-closed (in the sense that if fεEM(ℝ) and if f is bounded away from zero on ℝ, then its inverse f-1 lies in EM(ℝ)) if and only if the associated sequence A = {An = (Mn/n!)1/n} is almost increasing (i.e. Am ≤ KAn for all m ≤ n, where K > 0 is a constant independent of m and n).
On the p-approximate property for hypersurfaces of ℝn
Authors: Guo Kanghui
Published: October 2011

Let S(ℝn) be the space of Schwartz class functions and S'(ℝn) be the dual space of S(ℝn). Given a k-dimensional manifold M in ℝn with area (in case k = 1, M is a curve with length), then for 1 ≤ p ≤ ∞ we say that M has the p-approximate property of for each TεS'(ℝn) with supp T⊆M, and εLp(ℝn), we can find a sequence of measures {Tj,j = 1,2,…} on M, absolutely continuous with respect to the area measure on M, such that ∥j-∥p → 0 as j → ∞.
Continuity of the generalized kernel and range of semi-Fredholm operators
Authors: Searcóid M. Ó , West T. T.
Published: October 2011

Let X denote a Banach space over the complex field ℂ and let B(X) be the Banach algebra of all bounded linear operators on X. If T ε B(X), we write n(T) = dim ker (T) and d(T) = codim T(X). Suppose that Y is a subspace invariant under T; then TY will denote the restriction of T to Y and Y the operator on X/Y defined by

Y: x/Y →(Tx)/Y
Small Riesz spaces
Authors: Buskes G. , van Rooij A.
Published: October 2011

Many facts in the theory of general Riesz spaces are easily verified by thinking in terms of spaces of functions. A proof via this insight is said to use representation theory. In recent years a growing number of authors has successfully been trying to bypass representation theorems, judging them to be extraneous. (See, for instance, [9,10].) In spite of the positive aspects of these efforts the following can be said. Firstly, avoiding representation theory does not always make the facts transparent. Reading the more cumbersome constructions and procedures inside the Riesz space itself one feels the need for a pictorial representation with functions, and one suspects the author himself of secret heretical thoughts. Secondly, the direct method leads to repeating constructions of the same nature over and over again.
Zeros of expansions in orthogonal polynomials
Authors: Iserles A. , Saff E. B.
Published: October 2011

The theory of bi-orthogonal polynomials is exploited to investigate the location of zeros of truncated expansions in orthogonal polynomials. It turns out that, subject to additional conditions, these zeros can be confined to certain real intervals. Two general techniques are being used: the first depends on a theorem that links strict sign consistency of a generating function to loci of zeros and the second consists of re-expression of transformations from [3] in an orthogonal basis.
Linear functionals and Markov chains associated with Dirichlet processes
Authors: Feigin Paul D. , Tweedie Richard L.
Published: October 2011

By investigating a Markov chain whose limiting distribution corresponds to that of the Dirichlet process we are able directly to ascertain conditions for the existence of linear functionals of that process. Together with earlier analyses we are able to characterize those functionals which are a.s. finite in terms of the parameter measure of the process. We also show that the appropriate Markov chain in the space of measures is only weakly convergent and not Harris ergodic.
Some eigenvalue identities for Brownian motion
Authors: McGill Paul
Published: October 2011

The general problem can be stated as follows. Take a Brownian motion Bt started at − x < 0, and consider the additive functional At = ∫L(a,t)m(da), where L(a, t) is the Brownian local time. We suppose that m = m+ — m−, where these are positive measures supported respectively on (0, ∞) and (— ∞, 0). Then, with the equalization time defined by T = inf {t > 0: At = 0}, we ask for an explicit evaluation of the law π (x,dy) = P−x[BT∈dy]. In [8, 9] we showed how π (x,dy) can be obtained by solving an integral convolution equation of Wiener-Hopf type. The method used there exploits a technique of Ray [10].
The incidence of pertussis hospitalizations among Japanese infants: excess hospitalizations and complications?
Authors: TAKEUCHI M. , YASUNAGA H. , HORIGUCHI H. , MATSUDA S.
Published: October 2011

We examined pertussis hospitalizations among infants aged <1 year between 2006 and 2008 using the nationwide inpatient database in Japan. A total of 660 infants hospitalized for pertussis were identified. Peak incidence occurred at age 1 month and infants aged 0–2 months (too young for pertussis vaccination) and ⩾3 months (eligible for at least one dose of vaccination) accounted for 44·5% and 55·5% of hospitalizations, respectively. Complications related to pertussis were found in 165 (25·0%) cases, including one death; the age at admission did not differ significantly between patients with and those without complications (mean age 4·1 vs. 4·5 months, P=0·12). Seventeen patients required mechanical ventilation. Of the 17 cases, 14 infants were aged <3 months and three infants were aged ⩾3 months. Our findings highlight that the vaccination schedule against pertussis may often be delayed in Japan.
THE ORIGIN OF ORTHOGRAPHIC HU FOR /W/ IN NAHUATL
Authors: Canger Una
Published: October 2011

Today a standard has emerged in the English speaking world for writing the language of the Aztecs. According to this standard the phoneme /w/ is written  in the position before a vowel, nahuatl, ahuacatl, ‘avocado.’ An alternative is to write /w/ with  (or ), a tradition which in the sixteenth century and onwards was common alongside of . I demonstrate that  misrepresents the pronunciation of the language then and now, and in uncovering its origin, I suggest that Pedro de Gante was the prime promoter of .
“REAL-TIME” CLIMATE EVENTS IN THE BORGIA-GROUP CODICES: TESTING ASSUMPTIONS ABOUT THE CALENDAR
Authors: Woolley Chris , Milbrath Susan
Published: October 2011

In the past decade, a number of prominent scholars have attempted to use astronomical data to place the images on page 27 of theCodex Borgiain “real-time.” This method has yielded some interesting results, but all of these authors have assumed that theCodex Borgiawas produced in accordance with the Aztec calendar. Given the probable origin of theCodex Borgiain the area bordering the Mixtec and eastern Nahua cultural areas, this assumption needs to be tested. This article compares weather-related images that have associated dates on Borgia 27–28 with tree-ring data and estimated maize yields from the Puebla area. Our research for this paper seems to confirm the use of the Aztec calendar in theCodex Borgia. By analyzing depictions of weather phenomenon relating to maize production, we also offer a fresh analysis of this well-known document, specifically arguing that a major drought is shown in a 1 Rabbit year, whereas the year 1 Flint is linked with a period of dryness following heavy rains, a condition sometimes linked with locust swarms like those on Borgia 27.
TECHNOLOGIES OF TIME: CALENDRICS AND COMMONERS IN POSTCLASSIC MEXICO
Authors: Brumfiel Elizabeth M.
Published: October 2011

This article explores how the 260-day divinatory calendar changed over the course of Mesoamerican history. I begin with a description of the day-count in an ethnographic context, twentieth-century highland Guatemala. I then examine the day-count as recorded in sixteenth-century historical documents from central Mexico. Ceramic motifs on Early-Middle Postclassic period pottery from Xaltocan, Mexico, guide an examination of the day-count in the eleventh through sixteenth centuries. This study concludes that despite its reputation as an exclusively elite institution, thetonalpohuallihas served commoner purposes for at least a millennium. Commoners were more knowledgeable and more active agents regarding cosmology than most Mesoamericanists have previously believed. This study concludes that comparative historical analysis, that is, the systematic search fordifferences, as well assimilarities, in the ethnographic, ethnohistorical, and archaeological records, enhances the contributions of ethnography and ethnohistory to Mesoamerican archaeology.
THE OBSIDIAN AND CERAMICS OF THE PUUC REGION: CHRONOLOGY, LITHIC PROCUREMENT, AND PRODUCTION AT XKIPCHE, YUCATAN, MEXICO
Authors: Braswell Geoffrey E. , Paap Iken , Glascock Michael D.
Published: October 2011

Archaeologists working in the northern Maya lowlands have faced persistent problems in establishing chronological precision and accuracy. In particular, it has proven difficult to create multi-phase chronologies for the Late and Terminal Classic periods. Investigators at Xkipche, a small Puuc site southwest of Uxmal, have employed both seriation and the typological approach to ceramic chronology. The results of the ceramic seriation suggest great persistence from the second century untila.d.1100, a continuity that is not supported by the Type-Variety approach to chronology. This report begins by reviewing the ceramic data, and then turns to another archaeological material, obsidian. Procurement patterns and production technology are discussed for the 182 obsidian artifacts collected during the first five seasons of the Projekt Xkipche. These data are compared with similar information gleaned from other sites in the northern Maya lowlands. Results of this obsidian analysis conflict with the absolute chronology proposed for the Xkipche ceramic sequence. Finally, a compromise ceramic chronology is proposed, one that is consistent with both obsidian and architectural data. This proposed chronology divides the seemingly monolithic Cehpech ceramic complex into three phases: Early Cehpech (a.d.550–700); Late Cehpech (a.d.700–900/950); and, Terminal Cehpech/Sotuta (a.d.900/950–950/1000).
WHY THE HEAD? CRANIAL MODIFICATION AS PROTECTION AND ENSOULMENT AMONG THE MAYA
Authors: Duncan William N. , Hofling Charles Andrew
Published: October 2011

Recent attempts to study cranial modification have suggested that the practice was a part of embodiment and socialization among the Maya. Comparison of colonial and modern Maya childbirth and socialization practices supports these arguments. We suggest that the next question to be asked is: “Why was the head specifically targeted for modification among the Maya?” This paper argues that one of the motivations behind cranial modification among the Maya was to protect newborns from injury. We present evidence from colonial documents and ethnographic studies on midwifery showing that animating essences resided in the head and that newborns were particularly at risk for soul loss and injury from evil winds. Further we present data on metaphoric polysemy between the human body and houses to argue that newborn humans were much like newly constructed houses in their susceptibility and that both required ritual ensoulment. The construction of the house roof parallels cranial modification. This likely has parallels in Classic Maya times, with some temple dedications and the construction of vaulted roofs with capstones, and suggests that the need to guard against soul loss has pre-Columbian roots.
Optimal Sequential Selection of a Unimodal Subsequence of a Random Sequence
Authors: ARLOTTO ALESSANDRO , STEELE J. MICHAEL
Published: October 2011

We consider the problem of selecting sequentially a unimodal subsequence from a sequence of independent identically distributed random variables, and we find that a person doing optimal sequential selection does so within a factor of the square root of two as well as a prophet who knows all of the random observations in advance of any selections. Our analysis applies in fact to selections of subsequences that have d+1 monotone blocks, and, by including the case d=0, our analysis also covers monotone subsequences.
Brain Glycogen Content and Metabolism in Subjects with Type 1 Diabetes and Hypoglycemia Unawareness
Authors: Öz Gülin , Tesfaye Nolawit , Kumar Anjali , Deelchand Dinesh K , Eberly Lynn E , Seaquist Elizabeth R
Published: October 2011

Supercompensated brain glycogen may contribute to the development of hypoglycemia unawareness in patients with type 1 diabetes by providing energy for the brain during periods of hypoglycemia. Our goal was to determine if brain glycogen content is elevated in patients with type 1 diabetes and hypoglycemia unawareness. We used in vivo13C nuclear magnetic resonance spectroscopy in conjunction with [1-13C]glucose administration in five patients with type 1 diabetes and hypoglycemia unawareness and five age-, gender-, and body mass index-matched healthy volunteers to measure brain glycogen content and metabolism. Glucose and insulin were administered intravenously over ∼51 hours at a rate titrated to maintain a blood glucose concentration of 7 mmol/L. 13C-glycogen levels in the occipital lobe were measured at ∼5, 8, 13, 23, 32, 37, and 50 hours, during label wash-in and wash-out. Newly synthesized glycogen levels were higher in controls than in patients ( P<0.0001) for matched average blood glucose and insulin levels, which may be due to higher brain glycogen content or faster turnover in controls. Metabolic modeling indicated lower brain glycogen content in patients than in controls ( P=0.07), implying that glycogen supercompensation does not contribute to the development of hypoglycemia unawareness in humans with type 1 diabetes.
Glu106 in the Orai1 pore contributes to fast Ca2+-dependent inactivation and pH dependence of Ca2+ release-activated Ca2+ (CRAC) current
Authors: Scrimgeour Nathan R. , Wilson David P. , Rychkov Grigori Y.
Published: October 2011

FCDI (fast Ca2+-dependent inactivation) is a mechanism that limits Ca2+ entry through Ca2+ channels, including CRAC (Ca2+ release-activated Ca2+) channels. This phenomenon occurs when the Ca2+ concentration rises beyond a certain level in the vicinity of the intracellular mouth of the channel pore. In CRAC channels, several regions of the pore-forming protein Orai1, and STIM1 (stromal interaction molecule 1), the sarcoplasmic/endoplasmic reticulum Ca2+ sensor that communicates the Ca2+ load of the intracellular stores to Orai1, have been shown to regulate fast Ca2+-dependent inactivation. Although significant advances in unravelling the mechanisms of CRAC channel gating have occurred, the mechanisms regulating fast Ca2+-dependent inactivation in this channel are not well understood. We have identified that a pore mutation, E106D Orai1, changes the kinetics and voltage dependence of the ICRAC (CRAC current), and the selectivity of the Ca2+-binding site that regulates fast Ca2+-dependent inactivation, whereas the V102I and E190Q mutants when expressed at appropriate ratios with STIM1 have fast Ca2+-dependent inactivation similar to that of WT (wild-type) Orai1. Unexpectedly, the E106D mutation also changes the pH dependence of ICRAC. Unlike WT ICRAC, E106D-mediated current is not inhibited at low pH, but instead the block of Na+ permeation through the E106D Orai1 pore by Ca2+ is diminished. These results suggest that Glu106 inside the CRAC channel pore is involved in co-ordinating the Ca2+-binding site that mediates fast Ca2+-dependent inactivation.
NAADP regulates human platelet function
Authors: Coxon Carmen H. , Lewis Alexander M. , Sadler Amanda J. , Vasudevan Sridhar R. , Thomas Andrew , Dundas Kirsten A. , Taylor Lewis , Campbell R. Duncan , Gibbins Jonathan M. , Churchill Grant C. , Tucker Katherine L.
Published: October 2011

Platelets play a vital role in maintaining haemostasis. Human platelet activation depends on Ca2+ release, leading to cell activation, granule secretion and aggregation. NAADP (nicotinic acid–adenine dinucleotide phosphate) is a Ca2+-releasing second messenger that acts on acidic Ca2+ stores and is used by a number of mammalian systems. In human platelets, NAADP has been shown to release Ca2+ in permeabilized human platelets and contribute to thrombin-mediated platelet activation. In the present study, we have further characterized NAADP-mediated Ca2+ release in human platelets in response to both thrombin and the GPVI (glycoprotein VI)-specific agonist CRP (collagen-related peptide). Using a radioligand-binding assay, we reveal an NAADP-binding site in human platelets, indicative of a platelet NAADP receptor. We also found that NAADP releases loaded 45Ca2+ from intracellular stores and that total platelet Ca2+ release is inhibited by the proton ionophore nigericin. Ned-19, a novel cell-permeant NAADP receptor antagonist, competes for the NAADP-binding site in platelets and can inhibit both thrombin- and CRP-induced Ca2+ release in human platelets. Ned-19 has an inhibitory effect on platelet aggregation, secretion and spreading. In addition, Ned-19 extends the clotting time in whole-blood samples. We conclude that NAADP plays an important role in human platelet function. Furthermore, the development of Ned-19 as an NAADP receptor antagonist provides a potential avenue for platelet-targeted therapy and the regulation of thrombosis.
Hypoxia-inducible factor-1 (HIF-1) promotes LDL and VLDL uptake through inducing VLDLR under hypoxia
Authors: Shen Guo-Min , Zhao Ying-Ze , Chen Ming-Tai , Zhang Feng-Lin , Liu Xiao-Ling , Wang Yi , Liu Chang-Zheng , Yu Jia , Zhang Jun-Wu
Published: October 2011

Metabolism under hypoxia is significantly different from that under normoxia. It has been well elucidated that HIF-1 (hypoxia-inducible factor-1) plays a central role in regulating glucose metabolism under hypoxia; however, the role of HIF-1 in lipid metabolism has not yet been well addressed. In the present study we demonstrate that HIF-1 promotes LDL (low-density lipoprotein) and VLDL (very-LDL) uptake through regulation of VLDLR (VLDL receptor) gene expression under hypoxia. Increased VLDLR mRNA and protein levels were observed under hypoxic or DFO (deferoxamine mesylate salt) treatment in MCF7, HepG2 and HeLa cells. Using dual-luciferase reporter and ChIP (chromatin immunoprecipitation) assays we confirmed a functional HRE (hypoxia-response element) which is localized at +405 in exon 1 of the VLDLR gene. Knockdown of HIF1A (the α subunit of HIF-1) and VLDLR, but not HIF2A (the α subunit of HIF-2), attenuated hypoxia-induced lipid accumulation through affecting LDL and VLDL uptake. Additionally we also observed a correlation between HIF-1 activity and VLDLR expression in hepatocellular carcinoma specimens. The results of the present study suggest that HIF-1-mediated VLDLR induction influences intracellular lipid accumulation through regulating LDL and VLDL uptake under hypoxia.
Biochemical insight into physiological effects of H2S: reaction with peroxynitrite and formation of a new nitric oxide donor, sulfinyl nitrite
Authors: Filipovic Milos R. , Miljkovic Jan , Allgäuer Andrea , Chaurio Ricardo , Shubina Tatyana , Herrmann Martin , Ivanovic-Burmazovic Ivana
Published: October 2011

The reaction of hydrogen sulfide (H2S) with peroxynitrite (a key mediator in numerous pathological states) was studied in vitro and in different cellular models. The results show that H2S can scavenge peroxynitrite with a corresponding second order rate constant of 3.3±0.4×103 M−1·s−1 at 23°C (8±2×103 M−1·s−1 at 37°C). Activation parameters for the reaction (ΔH‡, ΔS‡ and ΔV‡) revealed that the mechanism is rather associative than multi-step free-radical as expected for other thiols. This is in agreement with a primary formation of a new reaction product characterized by spectral and computational studies as HSNO2 (thionitrate), predominantly present as sulfinyl nitrite, HS(O)NO. This is the first time a thionitrate has been shown to be generated under biologically relevant conditions. The potential of HS(O)NO to serve as a NO donor in a pH-dependent manner and its ability to release NO inside the cells has been demonstrated. Thus sulfide modulates the chemistry and biological effects of peroxynitrite by its scavenging and formation of a new chemical entity (HSNO2) with the potential to release NO, suppressing the pro-apoptotic, oxidative and nitrative properties of peroxynitrite. Physiological concentrations of H2S abrogated peroxynitrite-induced cell damage as demonstrated by the: (i) inhibition of apoptosis and necrosis caused by peroxynitrite; (ii) prevention of protein nitration; and (iii) inhibition of PARP-1 [poly(ADP-ribose) polymerase 1] activation in cellular models, implying that a major part of the cytoprotective effects of hydrogen sulfide may be mediated by modulation of peroxynitrite chemistry, in particular under inflammatory conditions.
Metallothioneins protect cytosolic creatine kinases against stress induced by nitrogen-based oxidants
Authors: Chen Zhe , Li Jie , Zhao Tong-Jin , Li Xu-Hui , Meng Fan-Guo , Mu Hang , Yan Yong-Bin , Zhou Hai-Meng
Published: October 2011

The formation of intracellular nitrogen-based oxidants has important physiological and pathological consequences. CK (creatine kinase), which plays a key role in intracellular energy metabolism, is a main target of low concentrations of oxidative and nitrative stresses. In the present study, the interaction between cytosolic CKs [MM-CK (muscle-type CK) and BB-CK (brain-type CK)] and MTs [metallothioneins; hMT2A (human MT-IIA) and hMT3 (human MT-III)] were characterized by both in vitro and intact-cell assays. MTs could successfully protect the cytosolic CKs against inactivation induced by low concentrations of PN (peroxynitrite) and NO both in vitro and in hMT2A-overexpressing H9c2 cells and hMT3-knockdown U-87 MG cells. Under high PN concentrations, CK formed granule-like structures, and MTs were well co-localized in these aggregated granules. Further analysis indicated that the number of cells containing the CK aggregates negatively correlated with the expression levels of MTs. In vitro experiments indicated that MTs could effectively protect CKs against aggregation during refolding, suggesting that MT might function as a chaperone to assist CK re-activation. The findings of the present study provide direct evidence of the connection between the two well-characterized intracellular systems: the precisely balanced energy homoeostasis by CKs and the oxidative-stress response system using MTs.
Influence of protein histidine phosphatase overexpression and down‐regulation on human umbilical‐vein endothelial cell viability
Authors: Seeger Anna , Rose Karsten , Ma Nien Tze , Kremmer Elisabeth , Klumpp Susanne , Krieglstein Josef
Published: October 2011

PHP (protein histidine phosphatase) is expressed by mammalian tissues, particularly in blood vessel walls. We investigated whether PHP plays a significant role in endothelial cells. By Western blot and immunofluorescence analysis PHP was found in HUVEC (human umbilical‐vein endothelial cells). Overexpression of PHP by the use of a plasmid vector, pIRES2‐AcGFP1‐PHP, induced apoptosis in HUVEC. To exclude the possibility that increased cellular protein alone unspecifically caused cell damage, the inactive H53A mutant of PHP was also overexpressed as a control; it did not lead to apoptosis. Down‐regulation of PHP by the RNAi (RNA interference) technique did not affect cell viability. In conclusion, HUVEC are damaged by overexpression, but not down‐regulation, of PHP, suggesting a pronounced impact of the enzyme on the cells when its activity is increased.
Cytoskeletal reorganization mediates fluid shear stress‐induced ERK5 activation in osteoblastic cells
Authors: Li Peng , Ma Yan‐chao , Shen Hai‐li , Han Hua , Wang Jing , Cheng Hui‐juan , Wang Cui‐fang , Xia Ya‐yi
Published: October 2011

Mechanotransduction is a complicated process, of which mechanosensation is the first step. Previous studies have shown that the cytoskeleton plays a crucial role in mechanosensation and the mediation of intracellular signal transduction. However, the mechanism of mechanotransduction in the bone remains elusive. Here, we investigated the potential involvement of a novel MAPK (mitogen‐activated protein kinase) member, ERK5 (extracellular‐signal‐regulated kinase 5), in the response of osteoblastic cells to FSS (fluid shear stress). Our results demonstrated that ERK5 was rapidly phosphorylated in pre‐osteoblastic MC3T3‐E1 cells upon FSS, and the integrity and reorganization of the cytoskeleton were critical in this process, in which the cytoskeleton‐dependent activation of FAK (focal adhesion kinase) may be involved in the activation of ERK5 induced by FSS. Moreover, we found that cytoskeletal disruption led to significant down‐regulation of ERK5 phosphorylation, but had no effect on ERK5 nuclear localization. Furthermore, the cytoskeleton rapidly reorganized in response to FSS, but long‐time fluid load, even at a physiological level, led to cytoskeletal disruption, suggesting that other pathways may be involved in long‐term mechanotransduction. Taken together, our data provide new insight into the mechanisms of mechanosensation by highlighting the link between ERK5 activation and cytoskeletal reorganization in osteoblasts undergoing FSS.
Hepatogenic differentiation of mesenchymal stem cells in a rat model of thioacetamide‐induced liver cirrhosis
Authors: Hwang Shin , Hong Hea‐Nam , Kim Hee‐Sung , Park Se‐Ra , Won You‐Jin , Choi Sang‐Tae , Choi Dongho , Lee Sung‐Gyu
Published: October 2011

Implantation of bone‐marrow‐derived MSCs (mesenchymal stem cells) has emerged as a potential treatment modality for liver failure, but in vivo differentiation of MSCs into functioning hepatocytes and its therapeutic effects have not yet been determined. We investigated MSC differentiation process in a rat model of TAA (thioacetamide)‐induced liver cirrhosis. Male Sprague—Dawley rats were administered 0.04% TAA‐containing water for 8 weeks, MSCs were injected into the spleen for transsplenic migration into the liver, and liver tissues were examined over 3 weeks. Ingestion of TAA for 8 weeks induced micronodular liver cirrhosis in 93% of rats. Injected MSCs were diffusely engrafted in the liver parenchyma, differentiated into CK19 (cytokeratin 19)‐ and thy1‐positive oval cells and later into albumin‐producing hepatocyte‐like cells. MSC engraftment rate per slice was measured as 1.0–1.6%. MSC injection resulted in apoptosis of hepatic stellate cells and resultant resolution of fibrosis, but did not cause apoptosis of hepatocytes. Injection of MSCs treated with HGF (hepatocyte growth factor) in vitro for 2 weeks, which became CD90‐negative and CK18‐positive, resulted in chronological advancement of hepatogenic cellular differentiation by 2 weeks and decrease in anti‐fibrotic activity. Early differentiation of MSCs to progenitor oval cells and hepatocytes results in various therapeutic effects, including repair of damaged hepatocytes, intracellular glycogen restoration and resolution of fibrosis. Thus, these results support that the in vivo hepatogenic differentiation of MSCs is related to the beneficial effects of MSCs rather than the differentiated hepatocytes themselves.