cssi/SciSciGPT-SciSciNet huggingface dataset:
Renal bicarbonate reabsorption and hydrogen ion excretion in children with recurrent urinary tract infections. The effect of fluorohydrocortisone.

Abstract. Aperia, A., Berg, U. and Broberger, O. (Department of Paediatrics, Karolinska Institutet, S:t Goran's Children's Hospital, Stockholm, Sweden). Renal bicarbonate reabsorption and hydrogen ion excretion in children with recurrent urinary tract infections. The effect of fluorohydrocortisone. Acta Paediat Scand, 63: 209, 1974.–Delayed renal response to ammonium chloride induced acidosis appears to be the earliest detectable residual dysfunction in recurrent urinary tract infections. Control of renal acidifying mechanisms was' therefore studied in 11 girls with recurrent urinary tract infections, but with normal glomerular filtration rates. The renal response to ammonium chloride induced acidosis was normal in 7 and pathological in 4 children. Bicarbonate infusion studies demonstrated that the pathological response to the ammonium chloride load was due to depression of the renal bicarbonate threshold. When, however, the plasma bicarbonate level exceeded the normal renal threshold, i.e. 24.5 mEq/litre, the reabsorptive capacity for bicarbonate was the same in the patients with pathological and normal ammonium chloride tests. Treatment with tluorohydrocortisone resulted in an increase in bicarbonate reabsorption and hydrogen ion secretion in all patients studied. It is suggested that the low bicarbonate threshold in some patients depends on selective tubular damage in a limited number of nephrons. The enhancement of bicarbonate reabsorption by bicarbonate infusion and by fluorohydrocortisone suggests that in the majority of the nephrons renal acidifying mechanisms are intact. It is also suggested that fluorohydrocortisone acts on renal acidifying mechanism mainly by increasing the availability of sodium for exchange with hydrogen ions.
Partitioning of amino acids into a model membrane: capturing the interface.

Energetics of protein side chain partitioning between aqueous solution and cellular membranes is of fundamental importance for correctly capturing the membrane binding and specific protein–lipid interactions of peripheral membrane proteins. We recently reported a highly mobile membrane mimetic (HMMM) model that accelerates lipid dynamics by modeling the membrane interior partially as a fluid organic solvent while retaining a literal description of the lipid head groups and the beginning of the tails. While the HMMM has been successfully applied to study spontaneous insertion of a number of peripheral proteins into membranes, a quantitative characterization of the energetics of membrane–protein interactions in HMMM membranes has not been performed. We report here the free energy profiles for partitioning of 10 protein side chain analogues into a HMMM membrane. In the interfacial and headgroup regions of the membrane, the side chain free energy profiles show excellent agreement with profiles previously repo...
Effect of Environmental Tobacco Smoke on LDL Accumulation in the Artery Wall

Background Previous research has shown that exposure to environmental tobacco smoke (ETS) increases the risk of atherosclerosis. To test the hypothesis that exposure to ETS increases LDL accumulation in the artery wall, we developed a model to measure the rate of LDL accumulation in individually perfused rat carotid arteries after the artery had been perfused with plasma taken from rats exposed to ETS (ETS-plasma). Methods and Results Rats were exposed to ETS in a chamber in which steady-state sidestream smoke was continuously circulating. After exposure, blood from the animals was collected. Carotid arteries from unexposed rats were perfused first with normal plasma containing fluorescently labeled LDL. Then, the same arteries (10 arteries from five rats) were perfused with ETS-plasma plus fluorescently labeled LDL. Photometric measurements were made during perfusion of the arteries with fluorescently labeled LDL, and rate of LDL accumulation (mV/min) and lumen volume (mV) (volume of fluorescently labele...
Adaptive neural queue management for TCP networks

Active Queue Management (AQM) is a proven strategy to efficiently maintain queues and ensure high utilization of Transmission Control Protocol (TCP) network resources. The fundamental mechanism is to manage incoming packet rates at a router to prevent incipient network congestion. In this paper, we present an efficient neural network AQM system as a queue controller. The recurrent neural network has a Multi-layer Perceptron-Infinite Impulse Response (MLP-IIR) structure. Three distinct neural AQMs are trained under different network scenarios involving traffic levels. Selecting one of three neural AQMs is based on posterior probability history of traffic level. In addition, we investigate stochastic modeling of the network dynamics by a Dynamic Bayesian Network (DBN). This model allows implementation of a predictive AQM system in which queue dynamics are predicted and used for error prediction via online DBN estimation. Our AQM method is evaluated through simulation experiments both using an Ordinary Differential Equation (ODE) network model and using OPNET^(C). The simulation results demonstrate that our adaptive neural AQM outperforms Random Early Detection (RED) and Proportional-Integral-Derivative (PID) based AQM.
Fetal Origins of Cardiovascular Disease

After completing this article, readers should be able to: 1. Describe the relationship between ischemic heart disease and term birthweight. 2. Delineate the intrauterine factors that can lead to programming and an increased risk for coronary disease and hypertension. 3. Describe the intrauterine factors that lead to postnatal endothelial dysfunction that increases the risk for coronary disease. Cardiovascular disease kills more people in western countries than any other disease. Furthermore, it now is known that women are as vulnerable to heart disease as men. In fact, the number of women living with cardiovascular disease in the United States exceeds the number of men who have the disease. In addition, the number of men and women whose lifestyles are limited due to a failing heart or other cardiovascular disability is increasing. The American Heart Association predicts that in 2004, the total cost of cardiovascular disease will exceed the cost of any other disease at about $370 billion, mostly due to heart disease. No disease takes a toll on the human population like heart disease and stroke. Although the incidence of cardiovascular disease has decreased in the United States since about 1970, the incidence is increasing in developing countries. Heart disease and stroke accounted for the deaths of some 10 million people around the world in 2000. In upcoming decades, the burden of cardiovascular disease is expected to increase dramatically in most countries of the world. Thus, the developing world is seeing an epidemic of heart disease as was seen in the first half of the 20th century in the United States. Cardiac scientists generally agree that pathologic change in the coronary endothelium is the common initiating feature of disease. In fact, fatty streaks on the coronary endothelium may develop even before birth in some susceptible individuals. Although there is a standard “textbook” progression of …
Evaluation of tree canopy epiphytes and bark characteristics associated with the presence of corticolous myxomycetes

Certain species of myxomycetes (plasmodial slime molds) are regularly present with mosses, lichens, and algae. Corticolous myxomycetes were previously studied in the tree canopy, and observations suggested that species occurrence is patchy and species abundance may increase with the presence of bryophytes and lichens. The purpose of this study was to quantify the association of corticolous myxomycete species with percent cover of epiphytes and with bark characteristics, such as water absorption, bark thickness, and bark pH. Study sites were located in three temperate forests in the southeastern USA. The doubled rope climbing method was used to collect bark from trees and grapevines in a vertical transect up to 15 m above ground level. Moist chambers (374) were used to culture myxomycetes for 32 d. The percent cover of lichens, bryophytes, myxobacteria, and filamentous fungi were estimated in five 2 cm × 2 cm quadrats for 187 sample sites. Results showed no association between percent cover of epiphytes an...
Racial matching and service utilization among seriously mentally Ill consumers in the rural south

The authors examined racial matching between case manager and client for 677 seriously mentally ill consumers served through a rural community mental health center in the southeastern United States. Nonparametric statistics indicated that client-case manager dyads were more likely to be of the same race than of different races. Same-race dyads tended to have greater service utilization as indicated by a greater number of made appointments over the study period. An interaction was found for failed appointments where African Americans in same-race dyads were more likely to fail appointments, while caucasian consumers in same-race dyads were less likely to fail appointments.
Insulin reaction and the cerebral damage that may occur in diabetes

1. The clinical observations on a diabetic patient who suffered severe hypoglyce mie shock which resulted in residual cerebral damage and death the following year are reported. 2. Similar cases reported in the recent literature are reviewed. 3. The dangers of irreversible mental changes following insulin shock are pointed out. 4. The symptomatology, pathology, and mechanism of insulin action in hypoglycemia are briefly discussed.
An In Vivo Screen of Secreted Proteins Identifies Adiponectin as a Regulator of Murine Cutaneous Wound Healing

Skin wounds comprise a serious medical issue for which few pharmacological interventions are available. Moreover, the inflammatory, angiogenic, and proliferative facets of a typical response to a wound each have broader relevance in other pathological conditions. Here we describe a genomics-driven approach to identify secreted proteins that modulate wound healing in a mouse ear punch model. We show that adiponectin, when injected into the wound edge, accelerates wound healing. Notably, adiponectin injection causes upregulation of keratin gene transcripts within hours of treatment, and subsequently promotes collagen organization, formation of pilosebaceous units, and proliferation of cells in the basal epithelial cell layer and pilosebaceous units of healing tissue. The globular domain of adiponectin is sufficient to mediate accelerated dorsal skin wound closure, and the effects are lost in mice that are homozygous null for the adiponectin receptor 1 gene. These findings extend recent observations of a protective role of adiponectin in other tissue injury settings, suggest modulation of AdipoR1 for the clinical management of wounds, and demonstrate a new approach to the identification of regulators of a wound healing response.
Rural women's economic realities.

SUMMARY The economic position of many elders has improved over the past few decades. Several groups of elders remain disadvantaged, however, including nonmetropolitan elders and women in any setting. This study examines differences in household income and poverty rates for metropolitan and nonmetropolitan women ages 55 and over in 1970, 1980 and 1990. Comparison of median incomes for women the same age across birth cohorts reveals that much of the improvement in women's economic well-being occurs because younger cohorts have higher incomes when they enter older ages. There also is evidence that incomes decline as the cohort ages. Nonmetro women have lower incomes and higher poverty rates than metro women in every comparison, even when demographic characteristics are controlled. While the metro/nonmetro income gap declines from 1970 to 1980, it increases from 1980 to 1990. The largest income gap occurs for women ages 55 to 64 in 1990, the youngest cohort examined, offering no evidence to support convergenc...
On 3-colorings of E(K n )

Abstract Let f(s, k) be the least n such that if we 3-color E(Kn) there is either a matching of size s of the first color or a tree with k vertices in one of the other colors. We prove f(s, k)=max{s+k−1, 2s}.
Electric Quadrupole Transitions near A = 16 : the Lifetimes of the N 16 0.120-, F 18 1.125-, F 19 0.197-, and Ne 19 0.241-MeV Levels

Continuing a program to study $E2$ lifetimes in the neighborhood of $A=16$, we have remeasured the mean lifetimes of the following states: the 0.197-MeV level of ${\mathrm{F}}^{19}$; the 0.241-MeV level of ${\mathrm{Ne}}^{19}$; the 0.120-MeV level of ${\mathrm{N}}^{16}$; and the 1.125-MeV level of ${\mathrm{F}}^{18}$. We find (129.9\ifmmode\pm\else\textpm\fi{}2.3) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}9}$sec, (26.6\ifmmode\pm\else\textpm\fi{}1.2)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ sec, (7.58\ifmmode\pm\else\textpm\fi{}0.09) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}6}$ sec, and (221\ifmmode\pm\else\textpm\fi{}21) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}9}$ sec, respectively.
Totally laparoscopic abdominal aortic aneurysm repair

On the basis of our previous animal and clinical experience with laparoscopic intra-abdominal vascular reconstructions, and due to the prevalence of abdominal aortic aneurysms (AAA), we have recently broadened our scope to tackle more difficult aortic surgery laparoscopically. We present a case report of our first clinical experience with laparoscopic AAA repair using specialized laparoscopic vascular instrumentation. The patient was an 84-year-old hypertensive male with a 7-cm asymptomatic infrarenal abdominal aortic aneurysm that was discovered incidentally. He presented with postcoronary artery bypass grafting and had moderate chronic obstructive pulmonary disease (COPD). A spiral computed tomograph (CT) angiogram revealed an adequate infrarenal neck and aneurysmal involvement of the proximal iliac arteries. An eight-port transabdominal technique was used with the patient in the supine position. Proximal and distal control was achieved without difficulty. The aneurysm was excluded using endoscopic stapling devices, and an aortobiiliac reconstruction was performed with a 16 × 9-mm bifurcated dacron graft. Estimated blood loss was 1000 ml, and the operative time was approximately 7 hours. The patient was ambulating without assistance on postoperative day 3. Total hospitalization was 7 days (delayed secondarily to postoperative ileus). Minimal quantities of narcotics were required for analgesia. At 6-months follow-up, the patient has palpable peripheral pulses and no complications related to surgery. This case report shows that a completely laparoscopic approach to the abdominal aortic aneurysm is possible using instrumentation specifically designed for laparoscopic vascular surgery. The exact role that laparoscopic techniques will hold in vascular surgery remains to be determined because these procedures are time consuming and technically difficult.
Mindfulness-Based Cognitive Therapy With Older Adults: An Exploratory Study

An 8-week mindfulness-based cognitive therapy (MBCT) group for older adults with depression and/or anxiety is described. This article is based on an exploratory study of this therapeutic approach and changes in participants' symptoms associated with participation. Pre-post data from 5 MBCT groups showed significant improvements in reported anxiety, ruminative thoughts, and sleep problems and a reduction in depressive symptoms. Case examples are presented to illustrate these symptom changes. Findings showed that this nonpharmacological intervention is acceptable to older adults and is associated with positive changes. Suggestions are provided for both practitioners and researchers interested in using MBCT with older adults.
Reactions to Different Types of Forced Distribution Performance Evaluation Systems

We isolate and describe four key elements that distinguish different forms of forced distribution systems (FDS). These key elements are the consequences for low performers, differentiation of rewards for top performers, frequency of feedback, and comparison group size. We examine how these elements influence respondents’ attraction to FDS. Undergraduate students (n = 163) completed a policy capturing study designed to determine how these four FDS elements influence their attraction to FDS. We examine the relative importance of these elements that most influence attraction to different FDS, as well as individual attributes (i.e., cognitive ability, gender, and major) that may affect those preferences. Respondents were most attracted to systems with less stringent treatment of low performers, high differentiation of rewards, frequent feedback and large comparison groups. Consequences for low performers were nearly twice as influential as any other element. Respondents with higher cognitive ability favored high reward differentiation and males were less affected by stringent consequences for low performers. Before practitioners implement FDS, it would be prudent to consider all four elements examined in this study—with the treatment of low performers being the most salient issue. Future accounts of FDS should clarify the nature of these elements when reporting on FDS. Such precision will be useful in generating a knowledge base on FDS. We add precision to the discussion of FDS by identifying four key elements. This is one of the first studies to examine perceptions of FDS from a ratee perspective.
Temperature influence on the rate of passage of cucumber mosaic virus through the epidermis of cowpea leaves.

Abstract Primary leaves of cowpea were inoculated, detached and incubated on water agar in closed containers at 16°, 20°, 24°, and 28°C. At hourly intervals, a portion of the epidermis was removed from the left half of each of several leaves. The number of lesions produced in unit areas devoid of epidermis was compared with that in equal areas on the opposite leaf half. At any one temperature, lesion numbers increased in the area devoid of epidermis as the time between inoculation and removal of epidermis was extended. Progressively more incubation time, prior to removal of epidermis, was required for any lesions to develop in the stripped areas as the incubation temperature was decreased. Also, progressively more time was required for equal numbers of lesions to develop in stripped and unstripped areas as the incubation temperature was decreased. Results suggest that temperature directly influences rate of virus passage through epidermal cells into mesophyll cells. Optimum temperature for maximum lesion production was 20° while that for the most rapid rate of virus passage through the epidermis was 28°. Results of experiments with leaves intact on the plants indicated that low internal temperatures of leaves diminished the influence of high external air temperatures on rate of virus passage through the epidermis.
Properties of polystyrene/poly(dimethyl siloxane) blends partially compatibilized with star polymers containing a γ-cyclodextrin core and polystyrene arms

Abstract A star polymer with a γ-CD core and PS arms (CD-star) is used to partially compatibilize blends of the immiscible polymers polystyrene (PS) and poly(dimethylsiloxane) (PDMS). The mechanism of compatibilization is threading of the CD core by PDMS and subsequent solubilization in the PS matrix facilitated by the star arms. Films cast from clear solutions in chloroform exhibit large wispy PDMS domains, indicating that some dethreading of CD-star and agglomeration of PDMS takes place during the slow process of solvent evaporation. However, DSC and DMA data show that partial compatibilization takes place, as evidenced by a shift in the PS and PDMS Tgs toward each other. The shift in PS Tg is greater when CD-star is present compared to samples without CD-star. PDMS also tends to leach out of the solution-cast films during solvent evaporation and post-processing of the films. The amount of retained PDMS is significantly increased when CD-star is present. The DMA data also show that PDMS has a lower molecular mobility when CD-star is present.
NO Adsorption, Desorption, and Reduction by CH4 over Mn-ZSM-5

An investigation of the interaction of NO with Mn-ZSM-5 as well as the reduction of NO by methane has been conducted using in situ infrared spectroscopy and mass spectrometry. Adsorption of NO at room temperature on Mn 2+ results in the slow oxidation to Mn 3+ , with the simultaneous formation of N2O. During NO exposure the intensity of the band for Mn 2+ (NO) (1894 cm − ) decreases while that for Mn 3+ (O − )(NO) (1966 cm −1 ) increases. Elevating the temperature, or introducing O 2 , converts the Mn 3+ (O − )(NO) to NO 2 /NO 3 species. Adsorbed NO 2 /NO 3 species are more stable to high temperature than NO. During the reduction of NO by CH 4 in the presence of O 2 , NO 2 is formed via the oxidation of NO. Adsorbed NO 2 then reacts with CH4. Cyanide species are observed and found to react very rapidly with NO 2 , leading to the formation of N 2 and CO 2 . A series of elementary steps are proposed to account for the reduction of NO by CH 4 in the presence of O 2 . As a part of this mechanism, it is hypothesized that the formation of N2 and N2O occurs via the processes Mn 3 +(O − )(CN) + NO 2 → Mn 3 +(O − ) + CO 2 + N 2 , and Mn 3 +(O − )(CN) + NO 2 → Mn 2 + + CO 2 + N 2 O, respectively.
Arachidonic acid lipoxygenation may mediate interleukin‐1 stimulation of nerve growth factor secretion in astroglial cultures

Interleukin-1 beta (IL-1) stimulates by about fivefold NGF secretion from rat neonatal cortical astrocytes in primary culture. We investigated the possible intracellular second messenger mechanisms involved in the IL-1 induced NGF secretion. Basal NGF secretion did not require extracellular Ca2+, whereas Ca2+ was necessary for the maximal NGF secretion stimulated by IL-1 (10 units/ml). The protein kinase C activator TPA stimulated by sixfold NGF secretion, but in this case, TPA acted synergistically with IL-1 to increase NGF secretion. Treatment of cells with the phospholipase A2 inhibitor mepacrine (30 microM) inhibited basal (by 50%) and IL-1 stimulated (by 80%) NGF secretion. Indomethacin, a cyclooxygenase inhibitor, produced a slight increase in basal NGF secretion at low concentrations, while PGE2 (10 microM) inhibited basal and IL-1 stimulated NGF secretion. In contrast, treatment of cells with nordihydroguaiaretic acid (NDGA), a lipoxygenase inhibitor, blocked in a concentration-dependent manner (IC50 = 10 microM) IL-1 stimulation of NGF secretion. The leukotriene LTB4 increased basal NGF secretion and this effect was not additive with IL-1 when both agents were added at saturating concentrations, indicating a common mechanism of action for these two agents. Thus, one possible mechanism by which IL-1 stimulates NGF secretion from astrocytes is by activation of the phospholipase A2-lipoxygenase pathway.
Properties of cements mixed from liquids with altered water content

Abstract The water content of the liquids of silicate, zinc phosphate, and silicophosphate cements was altered within the range of plus 10 to minus 10 per cent. Tests were run on the cements mixed from these liquids and the results of these tests compared with data obtained by testing cements mixed from the unaltered liquids. The following observations are made: 1. The setting times of zinc phosphate and silicophosphate cements are increased with increases in water of the liquids whereas the setting time of silicate cements is increased by a decrease in the water content of these liquids. 2. Cements mixed with liquids having altered water content have reduced physical properties, such as a marked reduction in abrasion resistance and increased solubility. 3. The results of the investigation emphasize protection of cement liquids from alteration in water content in order to maintain maximum physical properties of the cement mixes.
An analytical model of the knee

Abstract A model of the human knee is described in which the cruciate, collateral and capsular ligaments are represented by thirteen elements. The coordinates of the attachment sites and the dimensions of the ligaments are made by in vivo and in vitro measurements. The stiffness of the model is then assessed at flexion angles between 0° and 90°, under varus load, valgus load, internal and external rotation and anterior and posterior displacement. The theoretical results are then compared to experimental results and good agreement is achieved. The relative effect of a given ligament is then investigated by eliminating the element in the model and comparing this to an actual test where the ligament is transected. The importance of the deep fibers of the medial collateral in the anterior-posterior, rotational and valgus directions is demonstrated. The function of the oblique fibers of the medial collateral is shown as is the rotational stability derived from the anterior cruciate ligament.
Transcriptional organization of the S10, spc and α operons of Escherichia coli

Abstract We have investigated the transcription patterns at the inter-operon regions between the S10 and spc , and spc and α ribosomal protein operons of Escherichia coli . Newly synthesized transcripts were characterized by RNase T1 protection experiments, and accumulated transcripts were mapped with S1 nuclease. With both techniques we found that about 75% of the RNA polymerases transcribing the S10 operon terminated at the position of a typical ϱ-independent terminator. In contrast, most or all RNA polymerases transcribing the spc operon continued into the α operon. Nevertheless, we observed that about 30% of the transcripts of the α operon were initiated at the α operon promoter.
Oxygenation properties of snake hemoglobin.

Natrix taxispilota hemoglobin has a very high oxygen affinity which depends upon p H in an unusual manner. The oxygen affinity increases slightly upon protein dilution, but the pK9s of the Bohr groups are unchanged. Oxidation promotes hemoglobin polymerization, which can be inhibited by prior treatment with iodoacetamide. Reaction with iodoacetamide also causes a slight increase in the oxygen affinity, no change in the pK9s of the Bohr groups, and a drastic reduction in heme-heme interaction.
Retention and 5' cap trimethylation of U3 snRNA in the nucleus

It is shown here that maturation of the m7G-capped precursors of U3 small nuclear RNA (snRNA) occurs by a previously unknown pathway. In contrast to the 59 m7G-capped precursors of other snRNAs, this RNA is not exported to the cytoplasm but is retained in the nuclei of Xenopus laevis oocytes, where it undergoes trimethylation of its 59 cap. The m7G caps of most snRNA precursors are trimethylated only after transport of the RNAs to the cytoplasm. The nuclear retention and maturation of this nucleolar RNA raises the possibility that other m7G-capped RNAs are also retained and modified in the nucleus.
Crater features diagnostic of oblique impacts: The size and position of the central peak

Using Magellan data, we investigated two crater characteristics that have been cited as diagnostic of oblique impacts: an uprange offset of the central peak in complex craters, and an increasing central peak diameter relative to crater diameter with decreasing impact angle. We find that the offset distribution is random and very similar to that for high-angle impacts, and that there is no correlation between central peak diameter and impact angle. Accordingly, these two crater characteristics cannot be used to infer the impact angle or direction.
Attempted asymmetric radiolysis of D , L -tryptophan with 32 P β radiation

In 1957 Vester1 suggested that the then recently discovered2,3 violation of parity in weak interactions might be ultimately responsible for the present unique chirality of asymmetric molecules in the biosphere. Since then there has been a growing number of investigations involving the longitudinally polarised electrons from natural β decay. Initial attempts4,5 to detect asymmetric effects in several synthetic and degradative organic reactions using a number of β emitters failed and it was not until 1968 that Garay reported6 that β radiation from 90Sr/90Y caused D-tyrosine to degrade more than L-tyrosine in alkaline aqueous solution. Studies have subsequently looked at the possible asymmetric interaction of β rays (or their bremsstrah-lung) from a variety of sources (for example 104Rh (ref. 7), 90Sr/90Y (refs 8,9), 14C (refs 10–12) 32P (ref. 13) and polarised electrons from an accelerator14,15) with a number of racemic or optically active substrates (usually amino acids). Conflicting results emerging from these and certain related experiments have been tabulated13. Perhaps the most striking positive report among these studies is the claim by Darge and coworkers13 that D,L-tryptophan (4.9 × 10−7 mol in 2 ml frozen (−25°C) aqueous solution) was 33% decomposed with a 19% relative enrichment of the D-enantiomer in the undestroyed residue by the action during 12 weeks of the β rays from 5 mCi of co-dissolved 32P phosphate. The 33% gross decomposition was estimated from the UV absorption spectrum, and the 19% optical enrichment from the optical activity of the crude diluted reaction mixture, as compared with L-tryptophan at the same concentration (∼10−5M). The observed optical rotations used in the latter calculation were minute, −0.0036° for L-tryptophan and +0.0007° ±0.0004° (average of 16 observations) for the crude diluted reaction mixture. Because the remarkably large asymmetric effect claimed was based solely on these small observed rotations, and as the results have already been used by others in additional calculations16, we thought it desirable to attempt to duplicate the observations of Darge et al.13. We report here the use of a different analytical technique to estimate the enantiomeric composition of the undecomposed residual tryptophan, namely, gas chromatography (GC). The significant advantages of GC over optical rotation for determining the enantiomeric composition of small amounts of an optically active component admixed with impurities have already been described17.
Intractable Sneezing as a Conversion Symptom

A literature review of reported cases of intractable sneezing reveals that intractable sneezing typically occurs in children or adolescents and is a manifestation of conversion disorder. Analysis of these cases demonstrates a number offeatures that are helpful in differentiating psychogenic from organic sneezing. Also discussed are aspects of patient management once a diagnosis of conversion disorder is established.
Hypoxia-inducible factor determines sensitivity to inhibitors of mTOR in kidney cancer

Inhibitors of the kinase mammalian target of rapamycin (mTOR) have shown sporadic activity in cancer trials, leading to confusion about the appropriate clinical setting for their use. Here we show that loss of the Von Hippel-Lindau tumor suppressor gene (VHL) sensitizes kidney cancer cells to the mTOR inhibitor CCI-779 in vitro and in mouse models. Growth arrest caused by CCI-779 correlates with a block in translation of mRNA encoding hypoxia-inducible factor (HIF1A), and is rescued by expression of a VHL-resistant HIF1A cDNA lacking the 5' untranslated region. VHL-deficient tumors show increased uptake of the positron emission tomography (PET) tracer fluorodeoxyglucose (FDG) in an mTOR-dependent manner. Our findings provide preclinical rationale for prospective, biomarker-driven clinical studies of mTOR inhibitors in kidney cancer and suggest that FDG-PET scans may have use as a pharmacodynamic marker in this setting.
CANOE: Opportunistic calibration assisted micro navigation in dense open environments

Crowded musical concerts (and open densely crowded environments in general) pose significant hurdles to people trying to navigate to their family and friends. Calls get frequently dropped due to crowd spikes and loud noise makes cellular voice communication cumbersome. Low visibility in such dense environments render traditional navigation solutions ineffective. Global Positioning System (GPS) and Pedestrian Dead Reckoning (PDR) based systems are known to be error prone and inefficient for such micro-navigation scenarios. Incorrect and delayed position fixes result in high convergence time and frequent oscillating about the route to the destination, leading to a frustrating user experience, specially in dense crowd. To address the dual issue of convergence and user experience we propose CANOE - a novel tunnel based navigation methodology which allows users the flexibility of using their own sense to wade through crowd, while concurrently using best effort opportunistic position fixes to constrain drifts. It also reduces the dependency of constantly looking at the phone for position updates and route information. Extensive simulation results show that our algorithm can achieve 2–4x improvement in convergence time and reduced oscillations under different crowd scenarios as compared to state-of-the-art approaches. We also conduct live experiments with a crowd of 22 people and 15 smartphones and find that CANOE can contain location drifts within 1–2m in signal degraded environments where PDR location drifts range around 6–7m for short walks of 25m.
Skills, Productivity and the Evaluation of Teacher Performance

We examine the measurement and prediction of worker productivity using a sample of teachers and school principals. We find that principals’ evaluations are positively associated with teachers’ estimated contributions to students’ test scores (value-added), and are better predictors of teacher value-added than are teacher credentials. Principals’ assessments of teachers’ cognitive and non-cognitive skills are strongly associated with principals’ overall teacher evaluations and to a lesser extent with teacher value-added. While past teacher value-added predicts future value-added, principals’ subjective ratings can provide additional information, particularly when prior value-added measures are based on a single year of teacher performance.
When, where, and how much? Expression of the Kv3.1 potassium channel in high-frequency firing neurons.

The Kv3.1 potassium channel gene is expressed in neurons that fire action potentials at high frequencies. Neurons that express this gene, such as auditory brain stem neurons, have high-threshold voltage-dependent potassium currents that activate and deactivate unusually rapidly, and whose characteristics match those of the Kv3.1 subunit expressed heterologously. The level of Kv3.1 expression in neurons is regulated during development and by environmental stimuli. Pharmacological and computer modeling studies indicate that changes in the level of this channel alter the ability of a neuron to follow synaptic inputs at high frequencies. To understand the transcriptional mechanisms that control Kv3.1 expression, an initial characterization of the primary promoter for the Kv3.1 gene was carried out. This review summarizes current knowledge regarding Kv3.1 gene transcription and the roles of upstream regulatory elements in conferring cell-type specificity and long-term regulation by extrinsic factors. © 1998 John Wiley & Sons, Inc. J Neurobiol 37: 69–79, 1998
Hybridization of biotinylated oligo(dT) for eukaryotic mRNA quantitation

Quantitation of mRNA content in samples of total cellular RNA is required for the analysis of Northern blot hybridization to estimate the relative level of specific gene expression. Commonly used methods based on UV absorbance and dye staining measure only total RNA, and mRNA normalization by probing for mRNA levels of housekeeping genes, such as β-actin and glyceraldehyde-3-phosphate dehydrogenase, assumes a constant level of their expression, which, in fact, may vary as a function of cell proliferation and differentiation. We describe here a nonradioactive, slot-blotting method for quantifying eukaryotic mRNA levels using a biotinylated oligo(dT) probe, which hybridizes directly to the 3′-polyadenylated sequence of eukaryotic mRNAs. The method provides a more accurate estimation of mRNA content in total RNA samples and should be applicable for quantitative Northern analysis.
Aggregation Behavior of an Ultra-Pure Lipopolysaccharide that Stimulates TLR-4 Receptors

The innate immune systems of humans and other animals are activated by lipopolysaccharides (LPS), which are glucosamine-based phospholipids that form the outer leaflet of the outer membranes of Gram-negative bacteria. Activation involves interactions of LPS with the innate immunity-receptor comprised of toll-like receptor 4 in complex with so-called MD-2 protein and accessory proteins, such as CD14 and LPS binding protein. The Lipid Metabolites and Pathways Strategy (LIPID MAPS) Consortium has isolated in large amounts a nearly homogeneous LPS, Kdo2-Lipid A, and demonstrated that it activates macrophages via toll-like receptor 4. The active form of LPS, monomer or aggregate, is controversial. We have therefore examined the aggregation behavior and other physical properties of Kdo2-Lipid A. Differential scanning calorimetry of Kdo2-Lipid A suspensions revealed a gel-to-liquid crystalline phase transition at 36.4°C (Tm). The nominal critical aggregation concentration, determined by dynamic light scattering, was found to be 41.2 ± 1.6 nM below the Tm (25°C), but only 8.1 ± 0.3 nM above the Tm (37°C). The specific molecular volume of Kdo2-Lipid A, obtained by densitometry measurements was found to be 3159 ± 71 A3 at 25°C, from which the number of molecules in each aggregate was estimated to be 5.8 × 105. The aggregation behavior of Kdo2-Lipid A in the presence of lipoprotein-deficient serum suggests that Re LPS monomers and multimers are the active units for the immune system in the CD14-dependent and -independent pathways, respectively.
A GaAs memory device utilizing a buried JFET channel for nondestructive charge sensing

A new GaAs memory cell consists of a monolithic element in which a P-i-N-i-P epitaxial structure stores charge and a buried p-channel FET senses charge. Measured storage times up to 40 s were observed at 300 K with minimal effects on charge decay for applied drain voltages of V/sub DS/=+or-1.5 V. Electrical write and erase techniques are demonstrated and discussed. >
The effect of osteoporosis treatments on fatigue properties of cortical bone tissue

Bisphosphonates are commonly prescribed for treatment of osteoporosis. Long-term use of bisphosphonates has been correlated to atypical femoral fractures (AFFs). AFFs arise from fatigue damage to bone tissue that cannot be repaired due to pharmacologic treatments. Despite fatigue being the primary damage mechanism of AFFs, the effects of osteoporosis treatments on fatigue properties of cortical bone are unknown. To examine if fatigue-life differences occur in bone tissue after different pharmacologic treatments for osteoporosis, we tested bone tissue from the femurs of sheep given a metabolic acidosis diet to induce osteoporosis, followed by treatment with a selective estrogen reception modulator (raloxifene), a bisphosphonate (alendronate or zoledronate), or parathyroid hormone (teriparatide, PTH). Beams of cortical bone tissue were created and tested in four-point bending fatigue to failure. Tissue treated with alendronate had reduced fatigue life and less modulus loss at failure compared with other treatments, while tissue treated with PTH had a prolonged fatigue life. No loss of fatigue life occurred with zoledronate treatment despite its greater binding affinity and potency compared with alendronate. Tissue mineralization measured by microCT did not explain the differences seen in fatigue behavior. Increased fatigue life with PTH suggests that current treatment methods for AFF could have beneficial effects for restoring fatigue life. These results indicate that fatigue life differs with each type of osteoporosis treatment.
Microprocessor Techniques and Construction at the NSLS

A description is given of the microprocessor systems in use at the NSLS,1 which utilize Intel Multibus and NSLS-developed printed circuit boards. Ease of manufacturing and flexibility of developing different systems from a set of NSLS standard components will be emphasized, and the low cost factors of each system and the utilization of off-the-shelf components will be indicated.
Quantifications of error propagation in slope-based wavefront estimations

We discuss error propagation in the slope-based and the difference-based wavefront estimations. The error propagation coefficient can be expressed as a function of the eigenvalues of the wavefront-estimation-related matrices, and we establish such functions for each of the basic geometries with the serial numbering scheme with which a square sampling grid array is sequentially indexed row by row. We first show that for the wavefront estimation with the wavefront piston value determined, the odd-number grid sizes yield better error propagators than the even-number grid sizes for all geometries. We further show that for both slope-based and difference-based wavefront estimations, the Southwell geometry offers the best error propagators with the minimum-norm least-squares solutions. Noll's theoretical result, which was extensively used as a reference in the previous literature for error propagation estimates, corresponds to the Southwell geometry with an odd-number grid size. Typically the Fried geometry is not preferred in slope-based optical testing because it either allows subsize wavefront estimations within the testing domain or yields a two-rank deficient estimations matrix, which usually suffers from high error propagation and the waffle mode problem. The Southwell geometry, with an odd-number grid size if a zero point is assigned for the wavefront, is usually recommended in optical testing because it provides the lowest-error propagation for both slope-based and difference-based wavefront estimations.
Spectrogram-based formant tracking via particle filters

The paper presents a particle-filtering method for estimating formant frequencies of speech signals from spectrograms. First, frequency bands corresponding to the analyzed formants are extracted via a two-step dynamic programming based algorithm. A particle-filtering method is then used to locate accurately formants in every formant area based on the posterior PDF described by a set of support points with associated weights. Formant trajectories of voiced frames of a group of 81 utterances were manually tracked and labeled, partly for model training and partly for algorithm evaluation. In the experiments, the proposed method obtains average estimation errors of 72, 115, and 113 Hz for the first three formants, respectively, whereas the LPC based method induces 118, 172, and 250 Hz deviations. The experimental results show that the formants estimated by the proposed method are quite reliable and the trajectories are more accurate than LPC.
A half-factorial locally right Garside monoid and the inverse monoid of cofinite monotone partial bijections on {\mathbb {N}}^{*}

The half-factorial, locally right Garside monoid of cofinite monotone sequences on $${\mathbb {N}}^{*}$$ is considered in this paper. This is a right cancellative, left rigid Mobius monoid, and this monoid directs us to the inverse monoid of cofinite monotone partial bijections on $${\mathbb {N}}^{*}$$ . In a certain sense, the polycyclic inverse monoid is a 0-analogue of this derived inverse monoid. Similarities and differences between these two inverse monoids are presented involving Mobius categories, Leech’s construction, breaking processes, gauge inverse submonoids, etc.
Physics-based mathematical conditioning of the MOSFET surface potential equation

The traditional form of the implicit equation for the surface potential (/spl phi//sub s/) in metal-oxide-semiconductor field-effect transistors (MOSFETs) works well except near the flatband point /spl phi//sub s/=0 where it is both unphysical and ill-conditioned mathematically. This represents a significant difficulty for recent surface potential-based models, which require /spl phi//sub s/ evaluation from the accumulation to the strong inversion region. Detailed physical analysis combined with two-dimensional numerical simulations is used to develop a physics-based well-conditioned version of the surface potential equation.
Performance enhancement of heavy tailed queueing systems using a hybrid integration approach

This paper presents a hybrid integration approach for heterogeneous heavy tailed traffic from multiple classes over a channel of known capacity, where the service times follow lognormal distribution. Using our hybrid integration approach, we formulate a procedure that can minimize delay while improving the channel utilization. We show that this approach yields lower delays than either the integrated or segregated approach described in published literature.
Effects of initial eye position on saccades evoked by microstimulation in the primate superior colliculus: implications for models of the SC read-out process

The motor layers of the superior colliculus (SC) are thought to specify saccade amplitude and direction, independent of initial eye position. However, recent evidence suggests that eye position can modulate the level of activity of SC motor neurons. In this study, we tested whether initial eye position has an effect on microstimulation-evoked saccade amplitude. High (>300 Hz) and low (<300 Hz) frequency microstimulation was applied to 30 sites in the rostral part of the SC of two monkeys while they fixated one of six different locations. We found that the amplitude of the evoked saccades decreased with more contralateral initial eye positions. This effect was more pronounced in low frequency- compared to high frequency-evoked saccades, although it was present for both. Replication of these findings in head-free experiments showed that the effect of initial eye position was not due to physical constraints imposed by the oculomotor range. In addition to the effect of eye position on saccade amplitude, we also observed an increase in saccade latency and a decrease in the probability that microstimulation would evoke a saccade for low frequency stimulation at more contralateral eye positions. These findings suggest that an eye position signal can contribute to the read-out of the SC. Models of the saccadic pulse-step generator may need revision to incorporate an eye-position modulation at the input stage.
Civil War in the Kingdom of Benin, 1689-1721: Continuity or Political Change?

Using a combination of oral tradition and written documents, the authors show that Benin’s civil war was a fundamental transformation of political structure, and not simply an isolated struggle. Before 1640, Benin was centrally governed by its king with the assistance of a royally appointed administration. Difficulties in succession, coupled with changing trading patterns, allowed the administration to gain some independence and then to challenge the kings, taking away some power. The civil war matched different levels of the administration and the kings against each other, and transformed Benin from a centrally governed to a more collectively governed kingdom.
Anti-gD monoclonal antibodies inhibit cell fusion induced by herpes simplex virus type 1

Monoclonal antibodies directed against glycoprotein D of herpes simplex virus completely inhibited fusion of Vero cells infected with type 1 virus. In contrast, several monoclonal antibodies directed against other viral glycoproteins, including B, were ineffective or were only minimally inhibitory at the highest concentrations tested.