cssi/SciSciGPT-SciSciNet huggingface dataset:
The deposition of mercury in throughfall and litterfall in the lake champlain watershed: A short-term study

Abstract As part of an ongoing study of the atmospheric deposition of Hg in the Lake Champlain watershed, event throughfall, event precipitation, ambient, green foliage, and litterfall samples were collected and analyzed for Hg from a mixed hardwood forest in Underhill Center, VT, for six weeks during the months of August and September 1994. During this time period, the volume-weighted mean Hg concentration in throughfall (12.0 ± 8.5 ng l−1) was higher than in precipitation (6.5 ± 2.8 ng l−1). In August and September 1994, the total deposition of Hg in throughfall was estimated to be 3.1 μgm−2 (1.9 μg m−2 in precipitation) to the deciduous hardwood forests in the Lake Champlain basin. The mean Hg concentration in litterfall (53.2± 11.4 ng g−1) was significantly greater than the mean concentration in green foliage (34.2 +7.2 ng g−1), suggesting uptake of Hg from the atmosphere by foliage. Estimated annual litterfall deposition to the Lake Champlain basin was 13 μg m−2. This study suggests that throughfall and litterfall play a significant role in the cycling and deposition of Hg in the Lake Champlain watershed.
Extra value couponing—strategic implications for supermarkets†

This article outlines the numerous functions couponing performs for the manufacturer. However, extra value couponing is more than just couponing. The supermarket becomes an integral part of the promotional process. The changes created by extra value couponing have implications for various strategies and tactics of supermarkets. Conditions under which extra value couponing may be “profit-optimizing” are articulated.
Autoimmunity to Glutamate Receptors in Rasmussen's Encephalitis: A Rare Finding or The Tip of an Iceberg?

Neurological disorders demonstrate remarkable specificity in afflicting precise brain regions. They are most frequently sporadic in origin and they are devastating because of the progressive impairment of cognitive and/or motor functions. Our studies have found that some neurological diseases may actually reflect a dysfunction of the immune system in which highly specific autoantibodies are generated that bind neuronal glutamate receptors and directly affect their function in normal neurotransmission. Understanding at the molecular level how the immune system participates in neurological disease will ultimately lead to more effective therapeutic approaches to some of these disorders with presently unknown etiology. NEURO SCIENTIST 4:373-379, 1998
Density compensation, isocline shape and single-level competition models

Abstract Criticism of the Lotka-Volterra competition model implies that the theory of competition should be based upon more general concepts. It is suggested that the shape of the competitor isoclines can provide this basis. The relationship between the total density of a competitive community and species number depends crucially upon isocline shape. This has immediate relevance to the interpretation of the excess density compensation seen in some island communities, since if isoclines are sufficiently concave (curved towards the origin) then this phenomenon is expected to be the rule rather than the exception. These observations do not depend upon any specific model, but in order to determine the shape of isoclines in natural communities a link must be made between the biological processes of competition and isocline shape. To this end three types of single-level competition model are distinguished (additive, multiplicative and temporal resource models) depending upon how gains from resources interact in determining individual fitness. The models are based upon resource availability functions (RAFs), which are decreasing functions of the level of competition and determine the availability of each resource to each species. Provided that the argument of these functions is always a weighted sum of the number of competitors then in the case of the additive resource model the shape of the RAFs determines directly the shape of the isoclines. For the multiplicative model, the shape of the logarithm of the RAFs adopts this role. Analysis of a special case of the additive resource model suggests that concave isoclines are likely to predominate, and that the degree of concavity is of an order which minimizes the tendency of total numbers to increase with species number. In some circumstances, involving “scramble”-type competition and habitat selection, the expected concavity is sufficient to cause a decrease. In any event the expected occurrence of concave competition isoclines predicts a much higher incidence of excess density compensation (due to carrying capacity differences) than expected from any model having linear isoclines. The effect of shifting from an additive to a multiplicative resource model is to make the existence of purely concave isoclines less probable and to raise the possibility of purely convex isoclines. On the other hand, shifting from an additive resource model to a temporal resource model apparently has no such simple interpretation and specific predictions must await further analysis.
Phosphorylation of the MAP Kinases in the Smooth Muscular Cells of Abdominal Aortic Aneurysms

Objectives: Previous studies in our laboratory showed that the smooth muscular cells (SMCs) of the wall of abdominal aortic aneurysms (AAA) take part directly in the elastolytic activity characterizing the aneurysmal disease. The intracellular mechanisms responsible for this increased activity remain unknown. The objective of this study was to evaluate the degree of phosphorylation of several MAP kinases in SMCs from AAA, not dilated aorta (NDA) and atheromatous plaque. Materials and Methods: SMCs were put in culture from fresh tissues taken from surgeries for AAA, carotid endarterectomy (CE) and from NDA obtained during renal transplantations (n1⁄43 in each case). Flow cytometry made it possible to check that the SMCs were not contaminated by other cellular types. The SMCs were kept in culture and the proteins were extracted with each cycle. The degree of phosphorylation of p38, p42/ 44 and c-Jun N-terminal kinases (JNK) was evaluated by western blot. Results: The degree of phosphorylation of p38 was 6 times higher in the SMCs of AAA (p1⁄40.032). There was no significant difference between the SMCs of NDA and CE. There was no difference in the degree of phosphorylation of p42/44 between the various types of SMCs, although the cellular variability of the lines was high. The degree of phosphorylation of the isoform JNKp46 was significantly higher in the SMCs of AAA than in the SMCs of NDA (p1⁄40.027), but without significant difference with the SMCs of CE. However, the SMCs of CE presented a degree of phosphorylation of the isoform JNKp54 significantly higher than the aortic SMCs (p<0.01). Conclusion: In vitro, the SMCs of AAA seem to have an important stimulation of phosphorylation of MAP kinases p38 and JNK compared to the SMCs of NDA. This brings additional indices for the signaling pathways reached in the SMCs of AAA leading to an increased elastolytic activity and a degradation of the extracellular matrix.
Estrogen-induced tumorigenesis in hamsters: roles for hormonal and carcinogenic activities.

Based on the experimental studies presented herein, we have concluded there are hormonal and carcinogenic aspects to estrogens, both natural and synthetic, which are involved in renal tumorigenesis in the hamster. Hormonal aspects related to this tumor system are based on the presence of specific estrogen receptor in the untransformed kidney which is elevated by prolonged estrogen treatment. Moreover, antiestrogens, which inhibit estrogen receptor complex binding activity, completely block renal tumor induction by estrogens. Finally, estrogens were found to induce progesterone receptor in the hamster kidney and this induction can be inhibited by androgens and antiestrogens. Carcinogenic aspects related to renal tumorigenesis are suggested by the marked suppression of estrogen-induced kidney tumors by α-naphthoflavone. In addition, ethinyl estradiol, as potent an estrogen in the hamster as either DES of 17β-estradiol, induced only a very low renal tumor incidence. The finding that aryl hydrocarbon hydroxylase activity in the hamster kidney, but not the liver, is depressed markedly by estrogens and enhanced by androgenic hormone suggests involvement of the microsomal monooxygenase system in affecting estrogen metabolism and ultimately perhaps its carcinogenicity.
Hydrogen Exchange Reveals Differences between Bacterial Chemoreceptor Signaling States

Bacterial chemotaxis receptors form membrane-bound nanoarrays that sense and adapt to ligands from the environment. These arrays consist of receptors interacting at their cytoplasmic tips with a “baseplate” formed by the CheA kinase and CheW coupling protein, ≈300 A away from the periplasmic ligand binding sites. Receptor methylation at 4 glutamate residues in the cytoplasmic domain mediates adaptation to ongoing stimuli. To determine what ligand- and methylation-induced changes in the receptor cytoplasmic domain control the kinase activity, we have developed (1) methods to reconstitute native-like arrays of receptor cytoplasmic fragments, CheA, and CheW, and (2) a hydrogen exchange mass spectrometry (HDX-MS) method applicable to membrane-bound, multi-protein complexes. HDX-MS comparison of complexes with high and low kinase activity shows that differences localize to two functionally important subdomains of the receptor. Changes in the methylation subdomain that mediates adaptation are complex. The uniform exchange behavior of these peptides in the kinase-off complexes splits roughly in half in the kinase-on complexes, one fraction with slower exchange and the other with extremely rapid exchange (complete in 3 min). For the signaling subdomain that binds CheA and CheW, peptides exhibit protection from exchange at long times (16 hours) that is greater in the kinase-on state. HDX-MS of complexes prepared using different means of shifting the signaling state will reveal which changes correlate with kinase activity and will quantify stabilization of receptor subdomains and binding interfaces that contribute to receptor control of kinase activity. Thus HDX-MS provides an important tool in a hybrid approach for understanding structure and mechanism in membrane-bound, multi-protein complexes.This research supported by GM085288, and a University of Massachusetts fellowship to Seena Koshy as part of the Chemistry-Biology Interface Training Program (NRSA T32 GM08515).
Thyroid hormone regulates slow skeletal troponin I gene inactivation in cardiac troponin I null mouse hearts.

Two main troponin I genes, cardiac (cTnI) and slow skeletal (ssTnI), are expressed in the mammalian heart under the control of a developmentally regulated program. ssTnI is expressed first in embryonic and fetal heart, and is then downregulated by an unknown mechanism after birth. Unlike other contractile protein genes, ssTnI is not re-expressed during hypertrophy or end-stage heart failure in rats and humans. In the present study, we also show that ssTnI re-expression does not occur in hypertrophic mouse heart. To investigate ssTnI downregulation further, cTnI knockout mice were used to examine a possible role for thyroid hormone. Northern blot analysis of euthyroid animals showed a time-dependent loss of ssTnI mRNA that was similar for wild-type, heterozygous and homozygous cTnI mutant mice. In cTnI null mice made hyperthyroid by l -thyroxine, the duration of ssTnI expression assessed by both mRNA and protein content was abbreviated compared with the euthyroid group. Hyperthyroid cTnI null mice also died significantly earlier than euthyroids (postnatal day 14 v day 18). In cTnI null mice made hypothyroid by addition of phenylthiouracil to the drinking water, ssTnI expression was prolonged and mice survived until day 20 or 21. Overall, the results indicate that inactivation of the ssTnI gene occurs even in the absence of cTnI mRNA and protein indicating that these are not critical signals for ssTnI down regulation in the heart. In contrast, thyroid hormone influences the time course of ssTnI expression and the life span of cTnI null mice probably through a transcriptional regulation of ssTnI in the heart.
The Research Use of Astronomical Monographs

I explored the use of astronomical monographs used for research. After scanning 135 monographs (excluding conference proceedings and textbooks) listed in 2000-2003 issues of Physics Today and counting citations of them in 2000-2013 in ADS (Astrophysics Data System), I found that 67% of the monographs received fewer than 2 citations per year. The average citation rate for the 135 monographs is statistically the same as for ApJ papers. In contrast, only 41% of the ApJ papers produce fewer than 2 citations per year. ADS also counts the number of times each book or paper is read on-line. The average in 14 years is 181 ± 27 times for the monographs and 633 ± 47 times for ApJ papers. The total numbers of citations in 14 years for the monographs ranged from 0 to 711. I explored reasons for this range and only learned that it did not depend on (1) the numbers of book reviews published or (2) the scientific stature of the authors. I am unable to predict whether a monograph will be successful or not. The decreasing of references to monographs seems to be due to (1) monographs becoming so expensive that individuals and libraries cannot afford many of them, (2) readers seeming to prefer concise reviews, such as online searches and the Annual Reviews, and (3) most of the monographs having not been available free online.
Quinone-annulated N-heterocyclic carbene-transition-metal complexes: Observation of π-backbonding using FT-IR spectroscopy and cyclic voltammetry

A new N-heterocyclic carbene architecture comprising a 1,4-naphthoquinone annulated to 1,3-dimesitylimidazolylidene (NpQ−NHC) was synthesized in two high yielding steps from commercially available starting materials. The free NpQ−NHC was characterized (solution and solid-state) and was used to synthesize various Rh and Ag complexes that ranged in π-electron density. Enabled by the quinone moiety, the π-systems of these complexes were analyzed using infrared spectroscopy and cyclic voltammetry. In contrast to previous reports, π-backbonding was found to be non-negligible and was directly influenced by the metal's electronic character.
A note on generalizing the maximum lateness criterion for scheduling

Abstract In this paper we consider generalizing the objective criterion of minimizing maximum lateness in scheduling models. By isolating the properties of this objective function, we are able to show that certain approximation algorithms for the lateness model can be modified to handle a more general objective function, while preserving some performance guarantee. In particular, a special case of the more general criterion is minimizing the maximum weighted completion time of any job, and so our results highlight the close resemblance this objective function bears to minimizing maximum lateness.
Impedance-Model-Based SSR Analysis for Type 3 Wind Generator and Series-Compensated Network

Interaction between doubly fed induction generator (DFIG) Type 3 wind generators and series-compensated networks can lead to subsynchronous resonance (SSR) oscillations-a phenomenon observed in the real world. In this paper, impedance-based Nyquist stability criterion is applied to analyze the SSR phenomena. Impedance models of a DFIG along with its rotor-side converter (RSC) and grid-side converter, and a series-compensated network are derived in terms of space vectors. The DFIG impedance and the network impedance are analyzed to show the impact of wind speed, compensation level, and RSC current controller gain on SSR stability. Nyquist maps are also used to demonstrate the impact on SSR stability. Simulation studies are carried out to show SSR controller interaction. This paper successfully demonstrates that the interaction between the electric network and the converter controller is a leading cause of the SSR phenomena recently observed in wind generation grid integration.
The blackboard performance monitor: a mystery online

In late September 2005, the University of New Hampshire's Blackboard Learning and Community System began to slow down, disrupting the learning experience of UNH's entire academic community. We assembled an interdepartmental team to ascertain the cause of and ultimately solve this problem of stagnation. This cause itself was elusive, hidden within scores of possibilities, suggestions, and conjecture. Were online assessments overtaxing the servers? Are more servers needed? Was there a cascading effect in the internal processes, one impeding another, impeding another, etc? As questions, needs, and theories mounted, it became clear to us that comprehensive, objective, and quantifiable information would be essential to lift this fog of ignorance. Such necessity was the mother of the Blackboard Performance Monitor (BBPM), our custom designed, in-house system which collects data from the many facets of Blackboard and transforms that data into useful, web-based, graphical information. Initially, the BBPM provided us with many interesting and unfortunately unexpected answers, merely bringing yet more questions to light. But as the BBPM evolved with the needs of the team, it brought us closer and closer to our goal, until we eventually found the connection we sought, or in truth, the lack thereof.
Enterprise transformation to a service oriented architecture: successful patterns

This paper presents the initial findings from a series of case studies involving the enterprise transformation to service oriented architecture. Ten large enterprises were studied to determine how they were able to convert their legacy IT architecture. Particular interest was paid to business models, governance, enterprise architecture, change management, risk management, and technology. These cases were used to form a predictive model of success factors in transformation.
On the Diets of Neotropical Treeboas (Squamata: Boidae: Corallus)1

ABSTRACT. Nine species of the Neotropical boid genus Corallus are distributed from southeastern Guatemala to southeastern Brazil. Based largely on previously published papers, we accumulated 271 prey records for all species combined, and they comprised 2 frogs, 69 lizards (mostly Anolis), 1 snake, 65 birds, and 134 mammals (marsupials, rodents, bats). There is a conspicuous difference in diet between the two West Indian species (C. cookii and C. grenadensis) and species occurring on the mainland: juvenile and subadult boas from the West Indies prey almost entirely on anoles, whereas on the mainland (with the notable exceptions of C. batesii and C. caninus), those age classes prey largely on birds and bats. Four species (C. cookii, C. grenadensis, C. hortulanus, and C. ruschenbergerii) are vertebrate generalists and exhibit both active and ambush foraging modes. Adult C. batesii and C. caninus (and, perhaps, C. cropanii) are specialists on mammalian prey, may only utilize an ambush foraging mode, and were ...
Proof Without Words: Nonnegative Integer Solutions and Triangular Numbers

(2002). Proof Without Words: Nonnegative Integer Solutions and Triangular Numbers. Mathematics Magazine: Vol. 75, No. 5, pp. 388-388.
Age and skin structure and function, a quantitative approach (II): protein, glycosaminoglycan, water, and lipid content and structure

Background/purpose: The aging process has been studied with fervor recently, given our shifting demographics. As age's effects are so manifest in the skin's appearance, structure, mechanics, and barrier function, it is not surprising that much effort has been made in research to better understand them. Quantitative measurements permitted by bioengineering have allowed us to objectively and precisely study aging skin. These overviews piece together the immense amounts of information that have emerged from recent technological advances in dermatological research in order to develop a unified understanding of the quantitative effects of age on skin. Methods: We performed a literature search on age-related changes in protein, glycosaminoglycan (GAG), water, and lipid content and structure, searching Pub-med, Em-Base, Science Citation Index, and the UCSF dermatological library's collection of books on the topic of aging skin. Results: Collagen becomes sparser and less soluble in intrinsically aged skin, but is thickened and more soluble in extrinsically aged areas. Elastin is degraded slowly and accumulates damage with intrinsic aging; also, increased synthesis of abnormally structured elastin occurs in photoexposed areas. This leads to an age-related accumulation of aberrant elastoic material, clumped in the papillary dermis. Generally, age leads to increased folding and decreased interaction of proteins with water. Also, despite increased GAGs in aged skin, these are abnormally deposited on the elastoic material and cannot interact properly with water. Hence, in aged skin, water is found in the tetrahedron form, bound to itself rather than other molecules. Lipid content appears to decrease with age, although the proportion of different lipid classes seems to remain fairly constant. Conclusion: Much work remains to be carried out to reach a consensus on the effects of age on skin structure and function. Future studies would be benefited by increased standardization of skin sites tested, methodology, and increased sample sizes.
Conventional Crohn’s disease activity index definition of remission dose not predict patient’s perception of disease activity with high specificity

Conventional Crohn's disease activity index definition of remission dose not predict patient's perception of disease activity with high specificity
Benefits of β-Blocker Therapy for Heart Failure: Weighing the Evidence

Our understanding of factors contributing to the progression of heart failure has advanced dramatically over the past 2 decades. We have also gained considerable insight into the pharmacology of β-adrenergic receptor blockers (β-blockers). Based on this knowledge, we can now appreciate the potential of these drugs for the treatment of heart failure. Several β-blockers have been shown to be clinically effective in the treatment of heart failure. Critical evaluation of the evidence from basic research studies, as well as clinical trials in patients with heart failure, helps to delineate the theoretical and clinical benefits of β-blockers.
The effect of blockade of κ-opioid receptors in the medial preoptic area on the luteinizing hormone surge in the proestrous rat

Abstract The present study examined whether blockade of κ -opioid receptors in the medial preoptic area (MPOA) prior to the critical period on the afternoon of proestrus could prematurely evoke an ovulatory luteinizing hormone (LH) surge, and if so, whether norepinephrine (NE) is involved in mediating this response. In the first experiment, push–pull perfusion of the MPOA with nor-binaltorphimine (nor-BNI), a specific κ -opioid receptor antagonist, was done in rats between 10.30 and 13.50 h on proestrus. To determine whether any resulting ovulation was due to a nor-BNI-induced increase in LH release, rats were injected with pentobarbital at 13.55 h to block the afternoon LH surge. In 7 of 10 rats, nor-BNI in the MPOA produced a large increase in LH release beginning between 12.30 and 13.30 h, and 5 of 7 ovulated. During MPOA perfusion with cerebrospinal fluid in our normal colony between 14.00 and 17.00 h, surges of LH release began in the majority of rats between 15.30 and 16.30 h. Thus blockade of MPOA κ -opioid receptors advanced the LH surge by 3 h. The next experiment examined the effect of NE synthesis inhibition with bis(4-methyl-1-homopiperazinylthiocarbonyl) disulfide (FLA-63), or α -adrenergic receptor blockade with phenoxybenzamine (PBZ), on the nor-BNI-induced LH response. In 5 of 6 vehicle-treated rats, blockade of MPOA κ -opioid receptors elicited a large increase in LH release and all 5 ovulated. In contrast, only 3 of 8 rats pretreated with FLA-63 had a large increase in LH release and ovulated, and PBZ prevented the nor-BNI-induced LH increase and ovulation in 4 of 4 rats. PBZ also prevented the afternoon LH surge and ovulation in 4 of 4 rats in our normal colony. Finally, HPLC measurement of NE levels in MPOA push–pull perfusate indicated no increase in NE release during the nor-BNI-induced or normal afternoon LH surges. These results indicate that antagonism of κ -opioid receptors in the MPOA can prematurely evoke an ovulatory LH surge prior to the critical period on the afternoon of proestrus. Furthermore, the nor-BNI-induced as well as the normal afternoon LH surges are dependent on the proper functioning of central noradrenergic neurons, but do not involve increased NE release within the MPOA.
Biomechanical Evaluation of Short-Segment Posterior Instrumentation With Crosslinks in an Unstable Human Burst Fracture Model

Unstable thoracolumbar burst fractures are serious injuries and their management remains controversial. Some authors advocate the use of short-segment posterior instrumentation (SSPI) for certain burst fractures which offers several benefits including preservation of motion segments; however, clinical studies have shown mixed results. Whether crosslinks contribute sufficient stability to this construct has not been determined, therefore the objective of this study was to evaluate the biomechanical characteristics of short-segment posterior instrumentation, with and without crosslinks, in an unstable human burst fracture model.Copyright © 2009 by ASME
Addition of allylstannanes to glycal epoxides. A diastereoselective approach to β-C-glycosidation

Abstract A new method for the synthesis of β - C -allyl glycosides has been developed for use in the synthesis of the spongipyran macrolides. Functionalized dihydropyrans are transformed to cis tetrahydropyrans via a two step process: i) epoxidation using dimethyldioxirane and ii) Lewis acid mediated epoxide opening with allylstannanes as nucleophiles. This protocol, which can be successfully applied to complex systems, augments the limited body of methodology available for the preparation of β-configured C -glycosides.
Binding site of amiloride to urokinase plasminogen activator depends on species.

Novel drug candidate is checked on its potency on animal models before it can advance to human phase of the research. Usually negative results on animal phase disqualify it. Targeting specific enzymes by small chemicals rises the question about appropriateness of this approach. As an example, the urokinase (uPA) is recognized as an important enzyme responsible for cancer metastasis and angiogenesis. It is therefore important to ask the question if small chemical will inhibit uPA of different species with the same or different potency. Using DNA sequence and known structure of uPA we have modeled 3D structures of uPAs for several different species. By theoretical calculations we have determined most probable structure of amiloride/uPAs complexes. Catalytic triad (B57, B102, B195) and specificity pocket (B187-B197, B212-B229) are highly conserved in all cases, and are the regions responsible for proteolytic activity and recognition of the substrate. Significant differences were observed in a different region (loop B93-B101), that we identified as binding site of amiloride to the tissue plasminogen activator ( tPA). Although tPA shares the same function of activating plasminogen and it is structurally similar to uPA. Amiloride is a specific inhibitor of uPA but does not inhibit tPA. Our study shows that predicted position of amiloride depends on species and in some cases was located, as expected, in the specificity pocked, but in the other cases close to the loop B93-B101. This location could weaken affinity of binding or prevent inhibition of uPA at all. Therefore, drug screening and elimination process based solely on animal study, without careful structural analysis, could lead to the elimination of potential drug for humans.
Traitement in situ d'anévrysmes infectieux fémoraux par interposition d'une greffe veineuse fémorale superficielle

Les anevrysmes infectieux de l'artere femorale necessitent un traitement chirurgical pour eviter la progression du sepsis et l'hemorragie. Certains chirurgiens recommandent un parage simple et une ligature de l'artere femorale alors que d'autres recommandent une reconstruction arterielle dans des cas selectionnes ou dans tous les cas en raison de preoccupations concernant un risque eleve d'amputation. La reconstruction in situ a ete consideree comme contre-indiquee en raison de preoccupation concernant des ruptures anastomotiques ou du greffon du fait d'une persistance de l'infection. Cependant, la veine femorale superficielle a ete utilisee avec succes comme remplacement in situ apres resection de protheses aortiques infectees. Nous presentons deux malades ayant des anevrysmes infectieux de l'artere femorale qui ont tous deux ete traites avec succes par une reconstruction in situ utilisant la veine femorale superficielle autogene.
An investigation of DIF mechanisms in the context of differential testlet effects

This study investigated differential item functioning (DIF) mechanisms in the context of differential testlet effects across subgroups. Specifically, we investigated DIF manifestations when the stochastic ordering assumption on the nuisance dimension in a testlet does not hold. DIF hypotheses were formulated analytically using a parametric marginal item response function approach and compared with empirical DIF results from a unidimensional item response theory approach. The comparisons were made in terms of type of DIF (uniform or non-uniform) and direction (whether the focal or reference group was advantaged). In general, the DIF hypotheses were supported by the empirical results, showing the usefulness of the parametric approach in explaining DIF mechanisms. Both analytical predictions of DIF and the empirical results provide insights into conditions where a particular type of DIF becomes dominant in a specific DIF direction, which is useful for the study of DIF causes.
Gamma knife radiosurgery for patients with nonfunctioning pituitary adenomas: results from a 15-year experience.

Purpose To evaluate the efficacy and complications of stereotactic radiosurgery for patients with nonfunctioning pituitary adenomas (NFA). Methods and Materials This was a retrospective review of 62 patients with NFA undergoing radiosurgery between 1992 and 2004, of whom 59 (95%) underwent prior tumor resection. The median treatment volume was 4.0 cm 3 (range, 0.8–12.9). The median treatment dose to the tumor margin was 16 Gy (range, 11–20). The median maximum point dose to the optic apparatus was 9.5 Gy (range, 5.0–12.6). The median follow-up period after radiosurgery was 64 months (range, 23–161). Results Tumor size decreased for 37 patients (60%) and remained unchanged for 23 patients (37%). Two patients (3%) had tumor growth outside the prescribed treatment volume and required additional treatment (fractionated radiation therapy, n = 1; repeat radiosurgery, n = 1). Tumor growth control was 95% at 3 and 7 years after radiosurgery. Eleven (27%) of 41 patients with normal ( n = 30) or partial ( n = 11) anterior pituitary function before radiosurgery developed new deficits at a median of 24 months after radiosurgery. The risk of developing new anterior pituitary deficits at 5 years was 32%. The 5-year risk of developing new anterior pituitary deficits was 18% for patients with a tumor volume of ≤4.0 cm 3 compared with 58% for patients with a tumor volume >4.0 cm 3 (risk ratio=4.5; 95% confidence interval=1.3–14.9, p = 0.02). No patient had a decline in visual function. Conclusions Stereotactic radiosurgery is effective in the management of patients with residual or recurrent NFA, although longer follow-up is needed to evaluate long-term outcomes. The primary complication is hypopituitarism, and the risk of developing new anterior pituitary deficits correlates with the size of the irradiated tumor.
Relationships between resting and total energy expenditure in injured and septic patients.

Objective:To quantify resting and total energy expenditure in patients who have suffered severe trauma and sepsis.Design:Prospective, unblinded, observational, nonrandomized study.Setting:Critical care unit of a Level I adult trauma center.Patients:Immediate posttrauma patients or trauma patients ex
Timing parallel programs that use message passing

Abstract Hoare's paper describing the theoretical framework in which to express algorithms for parallel programs using message passing has led to the development ofmany parallel processing systems. As more and more parallel algorithms are developed and implemented, there is a rising need for a mechanism to compare their relative speedup and scalability. Conventional techniques for accumulating timing data for sequential programs are not powerful enought to solve the special problems introduced by parallelism. In this paper we present a timing metholodolgy capable of accurately determining the execution time of parallel programs, independent of system loads. Further, this timing methodology is capable of acquiring timing data when the number of processes exceeds the number of physical CPUs. Through simulation this methodology also provides a means by which to study the behavior of a parallel program under an arbitrary hardware/software communications configuration.
Role of magnetic resonance neurography in brachial plexus lesions

Magnetic resonance neurography (MRN) is a relatively new imaging technique that is highly sensitive in detecting lesions in the peripheral nerves. We studied six cases of brachial plexopathies in which MRN played a pivotal role in making the correct diagnoses. All patients had clinical, nerve conduction, and electromyographic findings consistent with brachial plexus lesions. Four patients had brachial plexitis and two had multifocal demyelinating neuropathy presenting as brachial plexopathies. MRN in all patients showed edema, thickening, and T2 hyperintensities localized to the brachial plexus region. We conclude that MRN is a useful technique in evaluating patients with brachial plexus lesions, particularly in cases of brachial plexitis, where conventional magnetic resonance imaging is generally normal.
Exploration in the acquisition of geocentric location by Tzotzil children.

L'A. decrit le systeme de description locative geocentrique en tzotzil. Il examine le developpement de ce systeme en comparant son utilisation chez des adultes et des enfants. Ce systeme semble etre acquis aux environs de 4,6 ans
Separation of mouse testis cells by equilibrium density centrifugation in Renografin gradients

Abstract Mouse testis cells have been separated by equilibrium density centrifugation in gradients of Renografin. Intact testis cells were not damaged by the separation procedure provided that, following separation, the osmolarity was reduced gradually. The various cell types were identified microscopically and by 3 H-thymidine labelling with similar results. The present technique has demonstrated that significant variations in cell density occur during spermatogenesis. Approximately ten-fold enrichments of nearly all testis cell types were achieved by equilibrium density separation of testis cell suspensions. More homogeneous cell populations were prepared by density gradient centrifugation of cell fractions obtained from velocity sedimentation separations. Overall enrichments of spermatogonia, by 29-fold; pachytene spermatocytes, 45-fold; dividing meiotic cells, 170-fold; round spermatids, 30-fold; step 11–13 elongating spermatids, 12-fold; Leydig cells, 70-fold; and cytoplasmic fragments, 55-fold, were obtained. In this study, a method for preparation of cell suspensions was also developed to produce higher yields of spermatogonia and young primary spermatocytes; however, the density distribution of these cells was altered.
Distortion sensitivity of estimators of location

Robustness measures and procedures have traditionally been developed and implemented through the contamination model of Hampel et al. [2005, Robust Statistics: The Approach Based on Influence Functions, Wiley Series in Probability and Statistics (Vol. 114), New York: Wiley]. We present a distortion model that takes a symmetric probability density function and skews it infinitesimally in a specific direction thereby distorting every realisation of the distribution, a model based upon the work of Fechner [1897, ‘Th.(1897)’, in Kollektivmasslehre, Leipzig: Engelman]. Robustness to distortion of a symmetric signal is determined as the rate of change of the functional of an affine-equivariant location estimator under the Fechner model. The mean, median and Hodges–Lehman estimators are compared under this model.
Estimated cardiorespiratory response during marathon running.

Cardiorespiratory responses during marathon running (42.2 km) were estimated on nine nationally ranked marathon athletes. Oxygen consumption ([vdot]o2), ventilation ([vdot]E), and heart rate (HR) were predicted from competitive data (average speed) using individual regression equations derived from steady-state values measured in the laboratory. From these predictions, ventilation equivalent ([vdot]E/[vdot]o2) and oxygen pulse ([vdot]o2/HR) were calculated. Stroke volume (q), cardiac output ([Qdot]), and the arteriovenous oxygen difference (a-⫨O2 diff) were estimated as follows: q = q max = Vo2 max/[Hgb] × O2 capacity of Hgb × (SaO2 – S⫨O2) max × HR max; [Qdot] = q × HR; and a-⫨O2 diff = [vdot]o2/[Qdot]. The [vdot]o2 max, HR max, and [Hgb] were measured in the laboratory; (SaO2 - S⫨O2) max was as- sumed to be O.7. These steady-state estimates were evaluated with respect to the effects of race duration and environmental factors. It was concluded that q, [Qdot], and particularly HR are heavily stressed duri...
Hepatic Lipase Deficiency Delays Atherosclerosis, Myocardial Infarction, and Cardiac Dysfunction and Extends Lifespan in SR-BI/Apolipoprotein E Double Knockout Mice

Objective— SR-BI/apolipoprotein (apo) E double knockout (dKO) mice exhibit many features of human coronary heart disease (CHD), including occlusive coronary atherosclerosis, cardiac hypertrophy, myocardial infarctions, and premature death. Here we determined the effects on this pathology of hepatic lipase (HL) deficiency, which has been shown to significantly modulate atherosclerosis. Method and Results— The SR-BI/apoE/HL triple knockout (tKO) mice generated for this study lived significantly longer (37%) than corresponding dKO controls (average lifespans: 63.0±0.8 versus 46.0±0.3 days), despite their increased plasma cholesterol levels. At 6 weeks of age, compared with dKO mice, tKOs exhibited significantly less aortic root and coronary artery occlusive atherosclerosis, and improved cardiac structure and function. However, by 9 weeks of age the hearts of tKO mice exhibited lipid-rich coronary occlusions, myocardial infarctions, and cardiac dysfunction essentially identical to that of 6-week-old dKO mice. Conclusions— HL-deficiency delays the onset and/or progression of atherosclerosis via a SR-BI–independent mechanism. Extent of occlusive coronary arterial lesions was more closely associated with cardiac dysfunction and lifespan than the amount of aortic root atherosclerosis, suggesting that these occlusions in dKO mice are responsible for ischemia, myocardial infarctions, and premature death.
Enthesitis in an inception cohort of enthesitis-related arthritis.

Objective To describe an enthesitis-related arthritis (ERA) inception cohort and determine which entheses and joints are most commonly affected. Methods We reviewed a retrospective inception cohort study of children with ERA who were diagnosed and treated at The Children's Hospital of Philadelphia between November 2007 and December 2009. Results During the study period, there were 32 newly diagnosed ERA patients. Fifty-nine percent were male, and the median age at the date of initial evaluation was 12.5 years (interquartile range [IQR] 10.2–14.3 years). The median number of tender entheses at presentation was 2 (IQR 0–5), and 21 subjects (66%) had at least 1 tender enthesis. The most prevalent tender entheses were the patellar ligament insertion at the inferior pole of the patella, the plantar fascial insertion at the calcaneus, the Achilles tendon insertion at the calcaneus, and the plantar fascial insertion at the metatarsal heads. Enthesitis was most often symmetric. The median number of active joints was 2 (IQR 0–4). The most commonly affected joints were the sacroiliacs, knees, and ankles. Sacroiliitis, which was defined clinically, was most often symmetric, while peripheral arthritis was most frequently asymmetric. The odds of having active enthesitis at 6 months increased significantly with each additional tender enthesis at the initial evaluation. Conclusion Among pediatric patients with ERA, lower extremity enthesitis is prevalent at the time of diagnosis and is likely to persist 6 months later. Future studies should address standardization of the enthesitis examination, the pattern of enthesitis over time, enthesitis response to therapy, and the impact of enthesitis on quality of life.
Switching dynamics of IGBTs in soft-switching converters

Next generation of power semiconductor devices will be designed and optimized to meet the specific application requirements. Mixed-mode simulations are used to study the carrier dynamics in punch-through and nonpunch-through Insulated Gate Bipolar Transistor (IGBT) structures during soft- and hard-switching conditions. The simulation results are shown to qualitatively predict the measured bump in the tail current with varying output dv/dt conditions and excessive forward conduction voltage under varying di/dt conditions. A new physical effect termed "conductivity modulation lag" is shown to occur during turn-on under soft-switching conditions. This mechanism is caused by the fact that minority carrier injection into the base of the bipolar transistor significantly lags behind the rate at which drift region conductivity can be modulated. The proposed phenomenon leads to an inductive effect that results in dynamic voltage saturation during turn-on and causes excessive forward voltage drop. >
Regulatory B Cells (B10 Cells) and Regulatory T Cells Have Independent Roles in Controlling Experimental Autoimmune Encephalomyelitis Initiation and Late-Phase Immunopathogenesis

Experimental autoimmune encephalomyelitis (EAE) is a T lymphocyte-mediated autoimmune disease of the CNS. Significant roles for B cells and a rare IL-10-producing CD1d(high)CD5(+) regulatory B cell subset (B10 cells) have been identified during the initiation and progression of EAE. Whether and how the regulatory functions of B10 cells and FoxP3(+) T regulatory cells (Tregs) overlap or influence EAE immunopathogenesis independently has remained unanswered. This study demonstrates that the number of endogenous or adoptively transferred B10 cells directly influenced EAE pathogenesis through their production of IL-10. B10 cell numbers expanded quickly within the spleen, but not CNS following myelin oligodendrocyte glycoprotein(35-55) immunization, which paralleled B10 cell regulation of disease initiation. The adoptive transfer of myelin oligodendrocyte glycoprotein(33-35)-sensitized B10 cells into wild-type mice reduced EAE initiation dramatically. However, B10 cells did not suppress ongoing EAE disease. Rather, Treg numbers expanded significantly within the CNS during disease progression, which paralleled their negative regulation of late-phase disease. Likewise, the preferential depletion of B10 cells in vivo during disease initiation enhanced EAE pathogenesis, whereas Treg depletion enhanced late-phase disease. B10 cells did not regulate T cell proliferation during in vitro assays, but significantly altered CD4(+) T cell IFN-gamma and TNF-alpha production. Furthermore, B10 cells downregulated the ability of dendritic cells to act as APCs and thereby indirectly modulated T cell proliferation. Thus, B10 cells predominantly control disease initiation, whereas Tregs reciprocally inhibit late-phase disease, with overlapping B10 cell and Treg functions shaping the normal course of EAE immunopathogenesis.
Impedimetric Determinaton of Total, Mesophilic and Psychrotrophic Zounts in Raw Milk

A rapid impedimetric determination for total, mesophilic and psychrotrophic counts in raw milk showed correlations (between impedance detection times and standard plate counts) of -0.96, -0.95, and 0.96, respectively. Mesophiles were most often seen as the predominant population, the impedimetric method allowed for these samples containing above 1.0 × 105 CFU/ml to be screened out within 4 hr. Psychrotrophic levels of 1 × 105 CFU/ml and above were screened within 21 hr, while total concentration of samples containing above 1 × 105 CFU/ml were screened within 16 hr.
Efficient evaluation of arbitrary set-associative caches on multiprocessors

The authors propose a simple solution to the problem of efficient stack evaluation of LRU (least recently used) cache memories with an arbitrary two's power set-associativity on multiprocessors. It is an extension of stack evaluation techniques for all-associativity LRU cache on a uniprocessor. Special marker entries are used in the stack to represent data pages (also called data blocks or lines) deleted by an invalidation-based cache coherence protocol. A technique of marker-splitting is used when a data page below a marker in the stack is accessed. One-pass evaluation of memory access trace will yield hit ratios for all cache sizes and set associativities on multiprocessor caches in a single pass over a memory reference trace with the use of this technique. >
Acute posterior multifocal placoid pigment epitheliopathy with bilateral central retinal vein occlusion

Abstract PURPOSE: We examined a patient with acute posterior multifocal placoid pigment epitheliopathy and bilateral central retinal vein occlusion. METHOD: Case report. A 28-year-old woman presented with the typical findings of acute posterior multifocal placoid pigment epitheliopathy. One month after presentation, the patient developed bilateral central retinal vein occlusion. RESULT: Four months after presentation, resolution of the bilateral central retinal vein occlusion resulted in a corrected visual acuity of RE, 20/25 and LE, 3/400. CONCLUSION: Vasculitis, sometimes associated with acute posterior multifocal placoid pigment epitheliopathy, can affect the ciliary vessels that supply the optic disk. This may result in axoplasmic stasis and compression of the central retinal vein, leading to impending or complete central retinal vein occlusion.