cssi/SciSciGPT-SciSciNet huggingface dataset:
Organic chemistry: Natural polarity inverted.

The concept of umpolung describes the reversal of the naturally occurring electrostatic polarization of chemical groups. It has now been used to make single mirror-image isomers of nitrogen-containing molecules. See Letter p.445 Imines, carbon–nitrogen double bonds, act as electrophiles towards carbon nucleophiles in the synthesis of amines, but the range of synthesizable amines could be greatly extended if the carbon atom of the imine could be rendered electron-rich to allow it to act as a nucleophile towards a carbon electrophile. Li Deng and colleagues have developed a procedure that achieves just that. They report the discovery and development of new chiral phase transfer catalysts that promote highly efficient asymmetric reactions of imines and enals. The reaction provides a conceptually new and practical approach towards the synthesis of chiral amino compounds.
Pharmacologic evidence for the modulation of nociception by noradrenergic neurons.

Publisher Summary This chapter discusses the pharmacologic evidence for the modulation of nociception by noradrenergic (NA) neurons. Four major systems of NA neurons that modulate nociception have been described. Three of these systems are involved in producing antinociception, while the fourth enhances nociception. System of bulbospinal NA neurons that modulates nociception is located in the locus coeruleus (LC) and subcoeruleus regions of the dorsolateral medulla. Stimulation of these neurons produces antinociception and inhibition of spinal cord dorsal horn neurons activated by noxious cutaneous stimulation. The NA neurons located in the A1 nucleus, part of the lateral reticular nucleus of the ventrolateral medulla, constitute a second NA pain modulation system. Electrical or chemical stimulation of the neurons in the A1 region produces antinociception and inhibition of spinal cord dorsal horn neurons. A third bulbospinal NA system originates in the rostral part of the A5 nucleus and includes the A7 nucleus. Electrical stimulation of neurons in these regions produces antinociception that can be blocked by intrathecal injection of NA antagonists. The fourth system of NA neurons, located in the caudal A5 nucleus, projects to, and tonically inhibits spinally projecting neurons located in the ventromedial medulla (VMM).
Number of Polypeptide Components in Bacteriophage T2L Contractile Sheaths

Isolated purified contractile tail sheaths of bacteriophage T2L were analyzed for their carboxyl terminal amino acids by carboxypeptidase treatment and hydrazinolysis. Glycine and serine were identified as the only two carboxyl end groups. Using corrections for the yields of these two amino acids upon hydrazinolysis, we calculated that there are 154 (+/-30) moles of C-terminal glycine and 130 (+/-45) moles of C-terminal serine per mole of sheath. It appears likely that sheaths contain two types of polypeptide chains in equal numbers, probably 144 of each. The relation of these two components to the mechanism of sheath contraction is discussed.
A Language-Independent Approach to European Text Retrieval

We present an approach to multilingual information retrieval that does not depend on the existence of specific linguistic resources such as stemmers or thesauri. Using the HAIRCUT system we participated in the monolingual, bilingual, and multilingual tasks of the CLEF-2000 evaluation. Our approach, based on combining the benefits of words and character n-grams, was effective for both language-independent monolingual retrieval as well as for cross-language retrieval using translated queries. After describing our monolingual retrieval approach we compare a translation method using aligned parallel corpora to commercial machine translation software.
Varieties of self-reference

The significance of any system of explicit representation depends not only on the immediate properties of its representational structures, but also on two aspects of the attendant circumstances: implicit relations among, and processes defined over, those individual representations, and larger circumstances in the world in which the whole representational system is embedded. This relativity of representation to circumstance facilitates local inference, and enables representation to connect with action, but it also limits expressive power, blocks generalisation, and inhibits communication. Thus there seems to be an inherent tension between the effectiveness of located action and the detachment of general-purpose reasoning. It is argued that various mechanisms of causally-connected self-reference enable a system to transcend the apparent tension, and partially escape the confines of circumstantial relativity. As well as examining self-reference in general, the paper shows how a variety of particular self-referential mechanisms --- autonymy, introspection, and reflection --- provide the means to overcome specific kinds of implicit relativity. These mechanisms are based on distinct notions of self: self as unity, self as complex system, self as independent agent. Their power derives from their ability to render explicit what would otherwise be implicit, and implicit what would otherwise be explicit, all the while maintaining causal connection between the two. Without this causal connection, a system would either be inexorably parochial, or else remain entirely disconnected from its subject matter. When appropriately connected, however, a self-referential system can move plastically back and forth between local effectiveness and detached generality.
Questions and information systems

Contents: T.W. Lauer, A.C. Graesser, Introduction. M. LaFrance, Questioning Knowledge Acquisition. S.E. Gordon, R.T. Gill, Knowledge Acquisition With Question Probes and Conceptual Graph Structures. T.W. Lauer, E. Peacock, S.M. Jacobs, Question Generation and the Systems Analysis Process. A. Lipp, H.O. Nourse, R.P. Bostrom, H.J. Watson, The Evolution of Questions in Successive Versions of an Expert System for Real Estate Disposition. J.M. Carroll, M.B. Rosson, Design by Question: Developing User Questions Into Scenario Representations for Design. R. Mack, Questioning Design: Toward Methods for Supporting User-Centered Software Engineering. K.L. Lang, A.C. Graesser, S.T. Dumais, D. Kilman, Question Asking in Human-Computer Interfaces. A.C. Graesser, N. Person, J. Huber, Mechanisms that Generate Questions. K. Dahlgren, Interpretation of Textual Queries Using a Cognitive Model. J.M. Golding, J. Magliano, D. Hemphill, When: A Model for Answering "When" Questions About Future Events. A.C. Graesser, P.J. Byrne, M.L. Behrens, Answering Questions About Information in Databases. T.W. Lauer, E. Peacock, Question-Driven Information Search in Auditor Diagnosis. P.J. Steinbart, The Role of Questioning in Learning From Computer-Based Decision Aids. D.B. Paradice, A Question Theoretic Analysis of Problem Formulation: Implications for Computer-Based Support. A. Kass, Question Asking, Artificial Intelligence, and Human Creativity.
Feeding tube placement during cytoreductive surgery and heated intraperitoneal chemotherapy does not improve postoperative nutrition and is associated with longer length of stay and higher readmission rates.

Abstract Background Patients with colorectal cancer and peritoneal carcinomatosis (CRC/PC) may benefit from cytoreductive surgery and heated intraperitoneal chemotherapy (CRS/HIPEC). Nutritional support is frequently required for patients after CRS/HIPEC. It remains unclear if placement of feeding access is of benefit in regard to improving postoperative nutrition in this patient population. Materials and methods Patients with CRC/PC who underwent complete cytoreduction were evaluated. Preoperative and postoperative nutritional data and discharge outcomes were retrospectively recorded. The presence of a feeding tube and PCI scores were recorded by review of operative notes. Readmission rates were calculated for patients at 30 d and 60 d after discharge from hospital. Results Forty-one patients underwent CRS/HIPEC, 25 had feeding tube placement at the time of surgery. Weight loss was common after HIPEC as 38 of 41 patients demonstrated weight loss. The mean weight loss was 7.6%. total parenteral nutrition was required at discharge in four patients (7.9%); three of these patients had feeding access placed. There was no difference in the degree of weight loss between groups (7.1 ± 3.7% no tube versus 7.9 ± 5.8% patients with tube; P = 0.608). The mean decrease in albumin was 12.7% but was not significantly different in patients with feeding access and those without (10.0% versus 14.75%; P = 0.773). Sixty-day readmission rates were higher in patients with feeding tubes (36% compared with 0%, P Conclusions Significant nutritional loss is common after CRS/HIPEC for patients with CRC/PC. Feeding tube placement does not prevent this and appears to be related to higher readmission rates and longer length of stay.
Studies on the Heterogeneity of Lysine-rich Histones in Dividing Cells*

Abstract The heterogeneity of the lysine-rich histone from several mammalian cells has been studied. The molecules were cleaved with N-bromosuccinimide and separated into three fractions by exclusion chromatography. The three fractions were Fraction 1, the NH2-terminal peptide of molecular weight ∼6000 which proved to be highly heterogeneous upon electrophoretic analysis; Fraction 2, the COOH-terminal fragment, which consists of two molecular weight groups (14,500 and 15,500), both of which are additionally heterogeneous as was deduced from tryptic fingerprinting and analysis of arginine-containing peptides; and Fraction 3, a protein which had the same molecular weight as the intact, unreacted lysine-rich histone. However, it did contain a spirolactone and we deduce that it is the product of an abnormal N-bromosuccinimide cleavage reaction. It shows the same type of electrophoretic heterogeneity as is seen for unreacted histone.
Indicadores fisicoquímicos y biológicos del proceso de eutrofización del Lago Titikaka ( Bolivia )

Se evaluo el grado de avance del proceso de eutrofizacion del lago Titikaka por medio de la evaluacion de las macrofitas (pleuston y limnofitas), de la diversidad de fitoplancton, de parametros fisicoquimicos (pH, turbidez, DBO5, nitrogeno total y fosforo soluble) y microbiologicos (coliformes fecales termotolerantes) en cuatro localidades del lago. Los resultados mostraron un avance diferencial en el desarrollo del proceso de eutrofizacion en cada sitio: se clasifico un sitio como aguas de calidad minima, un sitio como calidad baja y dos como calidad media. La conjuncion de turbidez, DBO5, nitrogeno y fosforo se manifiesta como un buen indicador del grado de avance del proceso de eutrofizacion, mientras que la evaluacion de macrofitas y fitoplancton proporcionan datos valiosos sobre la perdida de biodiversidad.
Sustained reversal of right-to-left atrial septal defect flow after pulmonic valvuloplasty in an adult

A 60-year-old man with Noonan's syndrome presented with generalized weakness, dyspnoea, andparesthesias. He was known to have pulmonic stenosis and atrial septal defect with right-to-left shunting and had refused therapy for many years. On presentation there was cyanosis and the haematocrit was 63%. After phlebotomy he was treated with balloon valvuloplasty. There was marked reduction in the transpulmonic gradient and oximetric evidence for reversal of his right-to-left atrial septal defect flow. After 18 months follow-up he remained symptom free and had no rise in haematocrit, consistent with no return of right-to-left shunting.
Testing and Certification of Medium Voltage Control Centers to Arc Resistant Standards

Improved medium voltage control equipment designs, including enhanced structural protection systems, have continued to evolve in support of improved personnel protection. Recent changes to some standards, such as the NFPA-70E, have emphasized the need to look for improved safety compliance to mitigating the risks associated with the operation and maintenance of electrical equipment. The requirements for employee safe work practices have all targeted reducing the risks of electrical arc hazards. However arcs accompanied by explosions continue to occur in electrical systems. Factors such as inappropriate human interaction with the equipment, equipment malfunctions as a result of misuse or lack of regular maintenance or unforeseen events continue to contribute to the unexpected release of explosive electrical energy in the workplace. This paper outlines the details surrounding the testing of medium voltage (MV) control center equipment to permit it to be certified to present arc resistant standards. The intent of this paper is to improve the understanding of the dynamics of an arc fault and how new arc resistant equipment designs can reduce personnel from exposed to electrical arc hazards in industrial settings.
Modulation of IgM secretion and H chain mRNA expression in CH12.LX.C4.5F5 B cells by adrenocorticotropic hormone.

The murine B cell line CH12.LX.C4.5F5 (CH12 (5F5) expresses adrenocorticotropin (ACTH) receptors, which can modulate IgM secretion by these cells. Interestingly, the response to ACTH was concentration dependent, inducing IgM secretion at subnanomolar amounts and suppressing secretion at micromolar amounts. With the use of an enzyme-linking immunospot assay it was possible to demonstrate that the ACTH-induced increase in IgM secretion by CH12 (5F5) cells was caused at least in part by an increase in the number of cells secreting IgM. CH12 (5F5) cells activated with suboptimal concentrations of LPS demonstrated a similar biphasic response. ACTH at concentrations of 10(-13) to 10(-9) M augmented IgM secretion in LPS-activated cells as much as sixfold, whereas 10(-6) M ACTH slightly decreased LPS-induced IgM secretion. At the mRNA level, subnanomolar concentrations of ACTH increased microH chain mRNA expression up to twofold in unstimulated or LPS-stimulated CH12 (5F5) cells. Taken together, these studies show that physiologically relevant concentrations of ACTH can interact directly with receptors on these B lymphocytes to enhance IgM secretion and microH chain mRNA expression. Although ACTH does increase intracellular cAMP levels in CH12 (5F5) B cells, it is unlikely that the induction of this second messenger pathway is by itself responsible for the ACTH induced B cell differentiation. The concentration of ACTH necessary to stimulate significant intracellular cAMP increases was 10- to 100-fold higher than that required to increase IgM secretion. Furthermore, CH12 (5F5) cells treated with varying concentrations of 8-bromo cAMP or cholera toxin were inhibited in their ability to secrete IgM. These results strongly suggest that the enhancing effects of ACTH on CH12 (5F5) IgM secretion are via mechanisms independent of those mediated by cAMP.
Projections to achieve minimum surgical rate threshold: an observational study.

Abstract Background Recent work has indicated an increase in surgical services, especially in resource poor settings. However, the rate of growth is poorly understood and likely insufficient to meet public health needs. We previously identified a range of 4344 to 5028 operations per 100 000 population annually to be related to desirable health outcomes. From this and other evidence, the Lancet Commission on Global Surgery recommends a minimum rate of 5000 operations per 100 000 population. We evaluate rates of growth in surgery and estimate the time it will take to reach this minimum surgical rate threshold. Methods We aggregated 2004 and 2012 country-level surgical rate estimates into the 21 Global Burden of Disease (GBD) regions. We calculated mean rates of surgery proportional to population size and estimate rate of growth between these years. We then extrapolated the time it will take to reach a surgical rate of 5000 operations per 100 000 population based on linear rates of change. Findings All but two regions (central Europe and southern Latin America) experienced growth in their surgical rates during the past 8 years; the fastest growth occurred in regions with the lowest surgical rates. 14 regions representing 79% of the world's population (5·5 billion people) did not meet the recommended surgical rate threshold in 2012. If surgical capacity grows at current rates, seven regions (central sub-Saharan Africa, east Asia, eastern sub-Saharan Africa, north Africa and middle east, south Asia, southeast Asia, and western sub-Saharan Africa) will not meet the recommended surgical rate threshold by 2035; Eastern Sub-Saharan Africa will not reach this level until 2124. Interpretation The rates of growth in surgical service delivery are exceedingly variable, but the largest growth rates were noted in the poorest regions. Although this study does not address the quality of care, and rates of surgery are unlikely to change linearly, this exercise is useful to project how many years it could take regions to reach specific surgical rates. At current rates of growth, 4·9 billion people (70% of the world's population) will still be living in countries below the minimum recommended rate of surgery in 2035. A strategy for strengthening surgical capacity is essential if these targets are to be met as part of integrated health system development. Funding None.
Paternal isodisomy of chromosome 7 associated with complete situs inversus and immotile cilia.

The authors thank the family for their cooperation. This work was supported in part by the Baylor College of Medicine Mental Retardation Research Center (National Institute of Child Health and Human Development [NICHD] 2P30-HD24064) and Child Health Research Center (NICHD 1P30-HD27823) (to W.J.C.) and by a March of Dimes grant (to L.G.S.).
Use of the Anterolateral Thigh in Cranio-Orbitofacial Reconstruction

Objective. To detail the clinical outcomes of a series of patients having undergone free flap reconstruction of the orbit and periorbita and highlight the anterolateral thigh (ALT) as a workhorse for addressing defects in this region. Methods. A review of 47 patients who underwent free flap reconstruction for orbital or periorbital defects between September 2006 and May 2011 was performed. Data reviewed included demographics, defect characteristics, free flap used, additional reconstructive techniques employed, length of stay, complications, and follow-up. The ALT subset of the case series was the focus of the data reviewed for this paper. Selected cases were described to highlight some of the advantages of employing the ALT for cranio-orbitofacial reconstruction. Results. 51 free flaps in 47 patients were reviewed. 38 cases required orbital exenteration. The ALT was used in 33 patients. Complications included 1 hematoma, 2 wound infections, 3 CSF leaks, and 3 flap failures. Conclusions. Free tissue transfer allows for the safe and effective reconstruction of complex defects of the orbit and periorbital structures. Reconstructive choice is dependent upon the extent of soft tissue loss, midfacial bone loss, and skullbase involvement. The ALT provides a versatile option to reconstruct the many cranio-orbitofacial defects encountered.
OUR DISCIPLINE'S DEMOGRAPHIC FUTURES: RETIREMENTS, VACANCIES, AND APPOINTMENT PRIORITIES

Age profiles of geographers having varying topical and areal subfields are compiled using the Guide to Graduate Departments of Geography in the United States and Canada, 1983–1984 and the 1982 AAG Directory. Major retirement trends for the next 10 to 20 years suggest that replacement of faculty may raise key appointment issues and priorities that may significantly change the nature of academic geography.
The mating-type locus ofNeurospora crassa

The mating-type locus regulates choice of mating partner and the formation of mixed-mating-type heterokaryons inNeurospora crassa. These biological activities reflect the effects of the mating-type genes on several distinct biochemical pathways. Some elements of such pathways are probably common to many other fungi. An example of such a pathway would be the mating-type-specific pheromone production and response known inN. crassa whose components inSaccharomyces cerevisiae are well characterized. The mating-type locus has two alternative forms or idiomorphs. Themta idiomorph apparently encodes a single product, the MT a-1 polypeptide. The structure and DNA-binding activity of MT a-1 suggest that it is a transcriptional activator of specific mating-related genes. Vegetative incompatibility depends on a different mechanism of action because requirements for this activity can be separated from those for mating. Themt A idiomorph encodes three products. MT A-1 is likely to be a transcriptional regulator similar toS. cerevisiae α 1. MT A-2 and MT A-3 are likely to be transcriptional regulatory proteins active after fertilization. The mating-type genes show surprising cross-species activity, and are not likely to be primary species barriers within the genusNeurospora. The role of other components of the mating pathways in speciation and in life history evolution remain to be tested.
Factors Affecting the Glucose Response to Insulin Injection in Mares: Epinephrine, Short- and Long-Term Prior Feed Intake, Cinnamon Extract, and Omega-3 Fatty Acid Supplementation

Five experiments were conducted with mares to better define factors that might affect the assessment of insulin sensitivity via direct insulin injection, and to then apply this method of assessing insulin sensitivity to trials which tested two potential supplements for improving poor insulin sensitivity in horses. The experiments assessed the effects of the following: (1) previous administration of epinephrine, (2) overnight feed deprivation versus hay or pasture consumption, (3) 10-day acclimatization to hay in a dry lot versus pasture grazing, (4) cinnamon extract supplementation, and (5) fish oil supplementation on insulin sensitivity. Mares of known high and low insulin sensitivities were used in the first three experiments, whereas mares with low insulin sensitivities were used in the supplement trials. Epinephrine administration increased blood glucose concentrations (P < .05) and prevented the insulin-induced decrease in blood glucose concentrations in both sensitive and insensitive mares. Overnight feed deprivation decreased (P < .06) insulin sensitivity relative to overnight ad libitum access to hay, and both regimens resulted in reduced insulin sensitivity relative to overnight pasture availability; sensitive and insensitive mares responded similarly except when kept on pasture (P = .0854). Ten days of hay consumption in a dry lot reduced (P < .05) insulin sensitivity in insensitive mares, but not in sensitive mares, relative to pasture grazing. Supplementation with cinnamon extract or fish oil had no effect on insulin sensitivity of mares with known low insulin sensitivity under the conditions of these experiments.
Allogeneic Hematopoietic Cell Transplantation for Children with Sickle Cell Disease Is Beneficial and Cost-Effective: A Single-Center Analysis.

Limited data exist regarding health care utilization (HCU) in patients receiving allogeneic hematopoietic cell transplantation (alloHCT) for sickle cell disease. Financial data from 2002 to 2011 were analyzed for 26 alloHCT patients and 48 control subjects (referred but without alloHCT). HCU of alloHCT was determined over 3 time periods: pre-alloHCT, during alloHCT (day 0 to day +365), and post-alloHCT. The median total cost per patient during the alloHCT year was $413,000 inpatient and $18,000 outpatient. Post-alloHCT HCU decreased when compared with pre-alloHCT and control subjects. The median cost of post-alloHCT outpatient visits per patient was significantly less when compared with pre-alloHCT (P = .044). The median cost of post-alloHCT inpatient visits per patient approached significance when compared with those pre-alloHCT (P = .079). Sixteen post-alloHCT patients, 19 control subjects, and 14 unaffected siblings were surveyed using Pediatric Quality of Life Inventory and EuroQOL questionnaires; however, the questionnaire scores across all 3 patient groups were not statistically significant (P = .2638). When adjusted for health-related quality of life, the analysis suggested alloHCT has a positive impact on health-related quality of life over control subjects. These pilot data support our hypothesis that alloHCT in children with sickle cell disease reduces HCU compared with control subjects without alloHCT.
CMOS heater array for incubation environment cellular study

We have designed a serial interface heater array with biocompatible packaging. Several different adhesion factors were tested for each of the materials used in the packaging to determine the best overall surface preparation for cell culture on a commercially fabricated CMOS die with PDMS packaging. The heaters were individually tested to determine the variations over the array. The heater array was calibrated to determine resistance values for each element of the array. Once calibrated the heater array can be used to control the temperature of an arbitrary set of locations to any temperature up to 85degC. The array can also be used in incubation mode for either incubation or to maintain the cells during testing
Differential effects of grape seed extract against human colorectal cancer cell lines: The intricate role of death receptors and mitochondria

Failure of anti-cancer therapy in colorectal cancer (CRC) cells involves resistance to death mechanisms. We investigated grape seed extract (GSE) ability to target CRC cells and delineated the mechanisms involved in GSE-induced CRC cell death. GSE selectively induced apoptotic death in human CRC cells; efficacy increased as the metastatic potential of the cancer cells increased. Oxidative stress, loss of mitochondrial membrane potential, modulation of pro- and anti-apoptotic proteins, and involvement of both caspase-dependent/independent apoptotic pathways contributed to GSE-induced CRC cell death. GSE intervention may serve as a multi-targeted CRC therapeutic capable of inducing selective cancer cell death.
Whither structural biology

We know the basic principles of protein, RNA and DNA structure, and we have atomic coordinates of many proteins and RNAs. Structural biology must now expand the range of length and timescales on which we can represent the molecular reality of a cell. Structural molecular biology and structural cell biology must merge into a single discipline, and we must establish a lively intellectual complementarity with the nascent 'systems biology' of the cell.
Concentration-dependent respiratory response of guinea pigs to a single exposure of cotton dust

Eight groups of guinea pigs were exposed to cotton dust at concentrations of 2 to 27 mg/m3. Each exposure was for 6 hr. The pulmonary function of each animal was assessed prior to exposure, following exposure, and 18 hr following exposure. Tidal volume decreased while respiratory frequency increased in a concentration-dependent manner. These changes were amplified when the same measurements were conducted while the animals were breathing an atmosphere containing 10% CO2 in 19% O2 and 71% N2. Greatest response was noted at 18 hr postexposure. The concentration-response effects can be applied to evaluate the respiratory potencies of different cotton dusts grown under a variety of conditions.
The nature of statistical fluctuations with applications to cosmic rays

I. The square of the mean deviation D of the combined effect of several random processes releasing an average of x, y, z ... particles per unit time and producing a, b, c ... ion pairs, respectively, per particle, is D2=a2x+b2y+c2z+..., regardless of whether the separate effects are added or subtracted by the experimental arrangement. For tube-counters, point-counters, scintillation screens and particle counting chambers, a=b=c=1; for ionization chambers a, b, c ... are unequal. II. From the standpoint of statistical fluctuations, the use of two identical instruments in a differential circuit is inferior to the use of a single instrument. III. The natural observational limit for the measurement of x particles against a background of y particles is x=0.67(y)1/2. IV. The statistical fluctuations in the ionization produced by cosmic rays in a spherical ionization chamber are treated rigorously and the fluctuations due to heterogeneity of range and to showers are derived. V. Application to existing data shows that the showers observed in cloud-chamber photographs of the cosmic radiation are also present in the ionization chamber in about the same frequency and multiplicity as indicated by the cloud-chamber results. The tube-counter investigations of the cosmic-ray flux are also in agreement with the deductions from the statistical fluctuations in the ionization chamber. An upper limit of 70±10 ion pairs per cm in air at 1 atmosphere is set for the total ionization along the path of an individual cosmic-ray secondary. The size and the relative frequency of occurrence of showers is appreciably greater at 14,700 feet elevation than at sea level. These showers are quite distinct from the ionization bursts or Stosse observed by Hoffmann, Steinke and others.
Charge distribution of extended localized holes in Magnus' green salt

Abstract A simple microscopic model for the charge distribution of the localized dz2 holes along the pt chain in doped Magnus' Green Salt provides excellent agreement with the observed superhyperfine pattern. It is thus confirmed that the observed superhyperfine pattern is due to the interaction of the bound hole with the Pt nuclei along the Pt chain and not with the ligand nuclei.
Severe Ice Cover on Great Lakes During Winter 2008–2009

The North American Great Lakes contain about 95% of the fresh surface water supply for the United States and 20% for the world. Nearly one eighth of the population of the United States and one third of the population of Canada live within their drainage basins. Because of this concentration of population, the ice cover that forms on the Great Lakes each winter and its year-to-year variability affect the regional economy [Niimi, 1982]. Ice cover also affects the lake's abiotic environment and ecosystems [Vanderploeg et al., 1992] in addition to influencing summer hypoxia, lake effect snow inland, water level variability, and the overall hydrologic cycle of the region [Assel et al., 2004].
Human kidney thiopurine methyltransferase purification and biochemical properties

Thiopurine methyltransferase (TPMT) catalyzes the S-methylation of thiopurines and thiopyrimidines. Human kidney TPMT was purified over 300-fold and its biochemical properties were determined. TPMT was "soluble" and had a molecular weight of approximately 36,000 daltons as estimated by gel filtration chromatography. The pH optimum of the purified TPMT was 6.7. "True" Km values for 6-mercaptopurine (6-MP) and S-adenosyl-L-methionine (SAM), the two cosubstrates for the reaction, were 0.30 mM and 2.7 microM respectively. "Apparent" Km values for 6-thioguanine and 2-thiouracil, two other methyl acceptor substrates, were 0.55 and 2.0 mM respectively. Aliphatic thiol compounds were either poor substrates for TPMT or were not methylated. S-Adenosyl-L-homocysteine was a competitive inhibitor of TPMT when the varied substrate was SAM, and 6-methylmercaptopurine was a noncompetitive inhibitor with respect to 6-MP. Purified TPMT was neither activated nor inhibited by 1 mM Ca2+ or Mg2+, but exposure to reagents such as N-ethylmaleimide and ethacrynic acid that interact with sulfhydryl groups inactivated the enzyme. Tropolone inhibited TPMT with a Ki of approximately 0.85 mM. Finally, human kidney TPMT activity could be distinguished from human kidney thiol methyltransferase (EC 2.1.1.9) activity on the basis of subcellular distribution, substrate specificity, kinetic characteristics and differential sensitivity to inhibitors.
Neuroprotection and traumatic brain injury: theoretical option or realistic proposition.

Purpose of review Preclinical studies have shown that treatment to limit secondary cell damage can significantly improve outcome after traumatic brain injury. In contrast, neuroprotection trials in human traumatic brain injury have failed to convincingly demonstrate therapeutic benefit. Recent literature has begun to address this discrepancy between preclinical and clinical trials. Recent findings Perhaps the most important recent observations relate to the potential role of apoptosis in secondary brain injury. Because apoptosis peaks more than 24 h after injury, concepts about the therapeutic window for traumatic brain injury treatment have changed. Apoptosis and necrosis are in delicate balance and inhibition of one cell death pathway may enhance the other. This raises questions about the ultimate effectiveness of treatment strategies directed toward a single injury mechanism. In contrast to clinical head injury, which reflects a complex multi-factorial disorder, animal models are generally designed to address only a single injury component and are performed in genetically inbred animals of a single sex. Moreover, animal studies usually employ pretreatment or early posttreatment administration, examine moderate rather than severe injury, fail to examine brain drug levels or treatment optimization, and do not use an intent-to-treat methodology. Summary Recognition of these methodological differences between animal and human studies has led to new trial design proposals. For clinical studies, there should be better stratification of patients, a focus on moderate injury and earlier treatment, and larger sample sizes. Animal experiments should better parallel clinical studies and address therapeutic window and treatment optimization. Recognition of multiple cell death pathways should lead to new treatment strategies - including both combination drug treatment and drugs that affect multiple components of the secondary injury cascade.
EPR studies on phosphorylating particles from Azotobacter vinelandii.

Abstract EPR studies at 12 °K on phosphorylating particles at an intermediate reoxidation level revealed a complex signal (g-values of 11.31, 3.36 and 1.37) which was provisionally assigned to non-heme iron. Reoxidation also resulted in a high-spin ferric heme resonance (g values at 6.20, 5.86 and 5.48) assigned to a d-type hemoprotein. NADH-reduced particles revealed resonances attributable to three different iron-sulfide centers. The third center differed significantly in g values from the same center observed in mammalian phosphorylating particles.
Superconductivity and lattice parameters in the zirconium-molybdenum, zirconium-tungsten, hafnium-molybdenum and hafnium-tungsten alloy systems

Abstract Superconductivity and lattice parameters have been measured on annealed alloys of ZrMo 2 , ZrW 2 , HfMo 2 and HfW 2 . Polymorphism for HfMo 2 was reconfirmed and the compound was found to be superconducting at 0.07 °K in the C 15 structure and normal down to 0.05 °K in the C 36 modification. The C15 compounds ZrMo 2 , ZrW 2 and HfW 2 were normal down to at least 1.2 °K. The b.c.c. phase was investigated by rapid quenching from the melt. It was possible to obtain single phase b.c.c. alloys in the range 3–41 at.% Mo in ZrMo alloys and about 9 to at least 67 at.% Mo in HfMo alloys. The lattice parameters at room temperature for these alloys could be accurately determined and extrapolated to room temperature b.c.c. values for Zr and Hf. It was possible to obtain HfMo 2 alloys in three different crystal structures. The superconducting transition temperature is about 1 °K for the b.c.c. modification and decreases with decreasing lattice symmetry. The rapid quenching technique was less successful in the tungsten alloys, but superconductivity in the b.c.c. phase could be observed in all four alloy systems. A maximum in the transition temperature was found in all systems at an electron/ atom ratio between 4 and 5. In the ZrW system, a dip in the transition temperature versus concentration was observed at the composition of the compound ZrW 2 . Some aspects of the superconductivity in the b.c.c. phase are discussed. It is found that the rigid band model is a good approximation in the dilute Zr region. An extrapolation to b.c.c. Zr gives 1.5 °K as the estimate for the transition temperature.
Design of focused single-element (50 to 100 MHz) transducers using lithium niobate

This paper discusses two fabrication procedures used to build LiNbO3 single element ultrasonic transducers with center frequencies in the 50-100 MHz range. Transducers of varying dimensions were built for an f-number range of 1.5- 3.0. A conductive quarter wavelength silver epoxy matching layer, and a conductive silver epoxy backing, were used in all designs. The desired focal depths were achieved by either casting an acoustic lens on the transducer face or press-focusing the piezoelectric into a spherical curvature. For lens-focusing transducers the lens material EPO-TEK 301 was modeled as a second matching layer. The pressed-focused transducer design utilized parylene as the second matching layer. For devices that required electrical impedance matching, a low impedance transmission line coaxial cable was used. All transducers were tested in a pulse-echo insertion loss arrangement, whereby the center frequency, bandwidth, insertion loss, and focal depth were measured. Several transducers were fabricated with center frequencies in the 50 to 100 MHz range. The measured -6dB bandwidths and two-way insertion loss values ranged from 33% to 70% and 12.5dB to 23.0dB, respectively. Both the lens-focusing and press-focusing techniques were successful in producing the desired focal depth without significantly compromising device sensitivity and bandwidth.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Characterization of the primary structural homology between the 16 S ribosomal RNAs ofEscherichia coli andBacillus megaterium by oligomer cataloging

The 16 S ribosomal RNAs of twoProcaryotes, Escherichia coli andBacillus megaterium were characterized by oligomer cataloging (oligomers produced by T1 nuclease digestion), in an attempt to detect their primary structural homology and as an initial step in characterizing this homology. Oligomer sequence coincidence between the two catalogs far in excess of the random expected levels was observed. Statistically significant coincidence was most pronounced for the hexamers and pentamers, suggesting that the overall structure of 16 S ribosomal RNA may be such that conservation of large stretches of its primary structure (e.g. over eight nucleotides in length) is not in general essential.
A generous solution to a sticky problem

Sometimes “messy human affairs” will take precedence over a strict adherence to academic standards.
Mechanisms of excreta formation and elimination in turkeys and ostriches.

Undigested feed and precipitated uric acid are excreted together in domestic turkeys, whereas in ostriches, liquid urine then discrete fecal boli are excreted in rapid succession. Gross anatomy and physiology of the cloacal structures of these two species also differ, providing an explanation for the differences in their waste products. J. Exp. Zool. 283:478–479, 1999. © 1999 Wiley-Liss, Inc.
The Off-shell Koba-nielsen Formula

Abstract Starting with the Witten covariant string field theory and using conformal field-theoretic methods, the tree-level off-shell N-point tachyon amplitude in the open bosonic string is obtained. It is shown to agree on-shell with the Koba-Nielsen formula.
Decreased serum cotinine levels in smokers of both tobacco and marijuana as compared with smokers of tobacco only.

Serum and salivary cotinine levels were determined in tobacco smokers (n = 125) who smoked only tobacco (n = 47) or who smoked both marijuana and tobacco (n = 78) as part of a field study of the pulmonary effects of heavy, habitual use of marijuana alone or with tobacco. After adjustment for current daily amount of tobacco use and time since the last tobacco cigarette was smoked, the smokers of both marijuana and tobacco were found to have lower levels of cotinine than those who smoked only tobacco, in serum [258 +/- 113 ng/ml (S.D.) and 332 +/- 109, respectively; p = 0.003] and in saliva (331 +/- 170 and 395 +/- 170, respectively; p = 0.058). Serum cotinine showed a significantly negative relationship to the daily amount of marijuana currently smoked (p = 0.026). Possible explanations include inhibition by marijuana component(s) of the enzymes that participate in the conversion of nicotine to cotinine, differences in nicotine absorption patterns between the two groups of tobacco smokers, and acceleration of cotinine metabolism by marijuana smoking. Carefully controlled pharmacokinetic studies, not possible in a large-scale survey such as this one, are required both to confirm the differences in blood cotinine levels observed between the dual smokers and smokers of tobacco only and to define more clearly nicotine-marijuana interactions.
Ribosome run through of the termination codon in the absence of the ribosome releasing factor

The ribosome releasing factor (RR factor) which releases ribosomes from mRNA at the termination codon has been examined for its effects on the amino acid incorporation programmed by wild type R17 Phage RNA and amB2 R17 RNA. When RR factor was added at the beginning of the incorporation, there was no effect on the initial rate of incorporation but it reduced the final level of incorporation. The reduction of the final level of incorporation was more pronounced for histidine incorporation than for valine incorporation suggesting that the translation of the RNA polymerase cistron was more influenced by RR factor. These experiments were carried out under conditions where no reinitiation of protein synthesis occurred. In the presence of RR factor, suppressor tRNA functioned better for the incorporation of amino acids into proteins with amB2 R17 RNA than did wild type tRNA. No such differential effect of suppressor tRNA was observed in the absence of RR factor. This suggests that the ribosome has to be released from mRNA by RR factor in order for the amber mutation to be effective.
Learning to Apply Psychology: Didactic Training, Experience and Opinions About Behavior Modification

(1978). Learning to Apply Psychology: Didactic Training, Experience and Opinions About Behavior Modification. Teaching of Psychology: Vol. 5, No. 1, pp. 23-26.
Cognitive rating scales: A comparison of the mini‐mental state examination and the middlesex elderly assessment of mental state

The MEAMS (Middlesex Elderly Assessment of Mental State) is a relatively new scale specifically developed to detect intellectual impairment secondary to organic brain dysfunction in the elderly. In this study the MEAMS was compared with the MMSE (Mini-Mental State Examination), a widely known and commonly used brief cognitive rating scale, in a group of 60 elderly acute psychiatric inpatients. Scores on both scales were highly correlated. However, the MEAMS was shown to be more sensitive in the detection of mild cognitive impairment, and was more sensitive to the presence of focal brain lesions than the MMSE. In the second part of the study, a further 25 inpatients were assessed using both scales by six junior and staff-grade doctors, who then rated the scales according to various criteria. Despite taking slightly longer to administer, the MEAMS was rated superior overall by the medical staff. It is suggested that the MEAMS is a sensitive instrument acceptable to both patients and staff, and is suitable for routine use in an old age psychiatric setting.
US Foreign Policy and Its Processes

Nixon, Kissinger, and US Foreign Policy Making: The Machinery of Crisis. By Asaf Siniver. Cambridge: Cambridge University Press, 2008. 247 pp., $80.00 hardcover (ISBN-13: 978-0-521-89762-4). Scholarly verdicts on the contributions of Richard Nixon and Henry Kissinger to US foreign policy rest in part on their much studied diplomatic opening to China, completed later in the Carter administration. Equally important were their modifications in the structure of White House decision-making, especially as revealed in crises where miscalculations could and sometimes did worsen cold war tensions with the then USSR. In a book that originated as a doctoral dissertation, Asaf Siniver provides meticulous detail on four such crises, the incursion into Cambodia in 1970, the Jordanian crisis of 1970, the Indian-Pakistan war of 1971 and the Yom Kippur war of 1973. Others have analyzed them from a variety of theoretical perspectives. The author uses the cases to good advantage here in spelling out Alexander George's …
Engineered Nanolipoproteins as Biosynthetic Decoys for Pathogen-Binding

The ability to exogenously present cell-surface receptors in a synthetic system offers an opportunity to provide host cells with protection from pathogenic toxins. Practical implementations suffer from serious limitations, primarily because of difficulties in mimicking the role of the membrane micro-environment during the complex and dynamic pathogen-receptor interaction. To this end, we have developed reconstituted lipoprotein - nanometer-sized discoidal lipid bilayers of arbitrary composition bounded by apolipoprotein - to serve as a versatile, biocompatible and stable platform to house pathogen-binding receptors in a membrane-like environment. Our approach exploits the notion that a control of biophysical properties of the membrane micro-environment allows to modulate interactions between membrane-embedded receptors and their pathogenic (e.g., bacterial toxin) targets. We demonstrate here, using a Foerster Resonance Energy Transfer (FRET) based assay, that ganglioside GM1 receptors incorporated at controlled concentrations in reconstituted lipoprotein bind cholera toxin with greater affinity than liposome-based systems. Furthermore, fluorescence microscopy investigations of cholera toxin presented to populations of mammalian cells show that GM1-laden lipoprotein can function as decoys without harming healthy cells.
Online estimation of internal resistance and open-circuit voltage of lithium-ion batteries in electric vehicles

State-of-charge (SoC) and state-of-health (SoH) define the amount of charge and rated capacity loss of a battery, respectively. In order to determine these two measures, open-circuit voltage (OCV) and internal resistance of the battery are indispensable parameters that are obtained with difficulty through direct measurement. The motivation of this study is to develop an online, simple, training-free, and easily implementable scheme that is capable of estimating such parameters, particularly for the lithium-ion battery in battery-powered vehicles. Based on an equivalent circuit model (ECM), the electrical performance of a battery can be formulated into state-space representation. Also, underdetermined model parameters can be arranged to appear linearly so that an adaptive control approach can be applied. An adaptation algorithm is developed by exploiting the Lyapunov-stability criteria. The OCV and internal resistance can be extracted exactly without limitations of a system input signal, such as persistent excitation (PE), enhancing the method applicability for vehicular power systems. In this study, both simulations and experiments are established to verify the capability and effectiveness of the proposed estimation scheme.
Phosphorylation of Biologically active analogs of riboflavin.

SummarySeveral analogs of riboflavin selected because of their exceptional biological activity in the rat have been studied as substrates for rat hepatic flavokinase. All of the analogs were phosphorylated, but the rate of phosphorylation showed no correlation with type of activity or potency for these activities. Phosphorylation of a flavin analog may be a prerequisite for significant biological activity but phosphorylation of a flavin does not insure that the substance will be biologically active in the whole animal.