cssi/SciSciGPT-SciSciNet huggingface dataset:
Changing agriculture: Roles for food and nutrition educators

Giving dietary advice used to be simple. Nutrition educators used the Basic Four food group plan to teach people to eat a variety of foods. Prevention of nutritional deficiencies was the goal, and fortification of foods was a scientific breakthrough. Food and nutrition educators usually were part of a te am of home economists who focused on home preparation of nutrient-dense foods. During this era, North Americans were proud that their food supply was the safest in the world. A change in focus. About 1960, medical researchers be­ gan to study the relationship between chronic diseases and diet. As data began to accumulate about the rela­ tionship of chronic diseases to overconsumption of sorne foodstuffs, a radical shift in thinking took place among nutrition educators. Instead of focusing on the preven­ tion of nutrient deficiencies, nutritionists began to de­ velop programs on the prevention of chronic diseases. In order to do this, it was necessary to begin reading medical journals and to learn a whole new set of acronyms such as HDL (high-density lipoproteins), LDL (Iow-den­ sity lipoproteins), and VLDL (very low-density lipopro­ teins). Nutrition educators also had to learn to network with colleagues in the health professions, and to dem­ onstrate that their expertise was of value. The role of every nutrition educator has been profoundly changed by this shift in focus from the prevention of nutrient deficiencies to the prevention of chronic diseases. Another change in focus. Nutrition educators are now on the threshold of another major change in focus con­ cerning diet and health. Last year, we struggled to learn enough about Alar to answer questions about the safety of apples. There are more than 100 other commonly used agricultural chemicals. How can nutritionists prepare for future questions about the health risks of the different
IRIS Seismology Program marks 20 years of discovery

The year 2004 marked the twentieth anniversary of the Incorporated Research Institutions for Seismology (IRIS) Consortium and its four core programs: the Program for Array Seismic Studies of the Continental Lithosphere (PASSCAL), the Global Seismic Network (GSN), Education and Outreach (E&O),and the Data Management System (DMS). IRIS activities (www.iris.edu) are supported principally through the U.S. National Science Foundation's (NSF) Earth Sciences Instrumentation and Facilities Program, and through the community efforts of IRIS's more than 150 member institutions in the United States and abroad. The consortium provides fundamental capabilities for the exploration of the Earth's interior through the collection and distribution of seismographic data. PASSCAL is the IRIS facility program dedicated to seismographic data collection associated with temporary deployments using highly portable instrumentation.
Cause of increase in “lower esophageal sphincter” pressure after fundoplication

Several clinical and experimental studies have demonstrated that the distal esophageal high pressure zone is restored to normal following fundoplication. The response of this region to abdominal compression also returns to normal. The mechanism underlying these effects usually is attributed, without direct evidence, to restoration of neurohumoral response of the “lower esophageal sphincter” following fundoplication. Not all workers accept such explanation, however, preferring to view postoperative functional improvement as a simple mechanical effect of the fundoplication. If fundoplication somehow results in restoration of intrinsic resting tone and responsiveness of the “lower esophageal sphincter,” then ablation of the lower esophageal sphincter should interdict the effect. On the other hand, if the result of fundoplication is a simple mechanical one exerted through changes in intra-abdominal or intragastric pressure, then postoperative responses in the esophageal high pressure zone might be directly proportional to changes in intragastric or intra-abdominal pressure, even after ablation of the lower esophageal sphincter. The objective of the experiments reported here was to determine the change, if any, in the manometric response of the distal esophagus to “lower esophageal sphincter” ablation by total distal esophageal myomectomy followed by fundoplication.
Gallium nitride epitaxy on (0001) sapphire

Abstract Two-step epitaxy consisting of low-temperature GaN nucleation layers (NLs) and high temperature (HT) GaN overgrowths, deposited on sapphire (0001) by metal-organic chemical vapour deposition, has been examined by transmission electron microscopy and atomic force microscopy. Results indicate that NLs consist of faceted crystalline islands that exhibit a spread in rotation about the (0001) axis. These islands undergo a metamorphosis on annealing and become rounded. The lateral growth during HT deposition of GaN occurs by the attachment of atomic species to steps associated with the rounded islands, resulting in faceted flat-topped islands. Furthermore, growth occurs preferentially in certain regions which evolve into ‘growth patches’. These patches then grow vertically and laterally over the underlying subgrains. The coalescence of these patches produces a continuous GaN layer. The origins of threading dislocations (TDs) in GaN layers have also been investigated. Results show that the majority of T...
Food for Communist China: A U.S. Policy Dilemma, 1961―1963

In January 1961, the Kennedy administration encountered many for eign policy issues that required a wide range of abilities and expertise from the new president and his advisers. While primary attention was focused on immediate and critical issues such as the Bay of Pigs, the Cuban missile crisis, renewed antagonisms with the Soviet Union over the status of Berlin, and negotiations for a nuclear disarmament treaty, relations with China could not be ignored, especially since specula tion grew regarding the future course of America's policy from both domestic and international circles. Anticipation surrounding the pros pect of change was fueled by images of the young John F. Kennedy and his cabinet as "new frontiersmen." The administration promised to liberate the United States from past policies and offer innovative solutions to problems confronting the nation worldwide. In A Thou sand Days, Arthur M. Schlesinger, Jr. described Kennedy as "the first representative in the White House of a distinctive generation, the gen eration which was born during the First World War, came of age dur ing the depression, fought in the Second World War and began its public career in the atomic age."1 Thus, while members of the Kennedy team, with the profound expectations and sensibilities of a different generation, pronounced their intent to reconsider past policies, whether they could alter the course of Sino-American relations remained to be determined by subsequent interactions with, and the resulting per ceptions of, the government of the Republic of China (GRC) and the People's Republic of China (PRC). Despite the administration's proposed departure from past poli cies, Kennedy and his advisers could not easily dismiss recent events, especially those shaping the images of the Chinese Communists, who had gained control of the mainland in 1949, and the Chinese National ists who fled to Taiwan. Intervention in the Korean War from 1950 to 1953, the two offshore island crisis of 1954-55 and 1958, and support
Essay: Punitiveness as “Behavior Management”

Behavior management plans (BMPs) are temporary deprivation experiences that have been advertised as promoting the discontinuance of habitual misbehavior in institutions. In practice, these interventions are often invoked in retaliation or as punishment when individual inmates are uncooperative or troublesome. In settings that already offer a rock-bottom quality of life—such as segregation units in prisons—BMPs reliably call for intolerably stressful conditions that tend to compromise the mental health of persons who are subjected to these conditions. The cycle is predictably exacerbated when the behavior that is targeted is symptomatic of mental illness in the first place, as is frequently the case.
Globalización, desmodernización y el retorno de los monstruos

O principal objetivo deste ensaio e refletir sobre como o processo de globalizacao e interpretado e representado por distintos imaginarios, tais como : publicos, oficiais, vernaculares e pelas zonas de exclusao.
Clinical responses to sildenafil in Waldenstrom's macroglobulinemia

Waldenstrom's macroglobulinemia (WM) is an incurable B-cell malignancy. Interestingly, an unusual response activity was observed in 5 patients with WM that appeared related to their use of sildenafil, a phosphodiesterase inhibitor used to treat erectile dysfunction. One patient demonstrated a complete remission, and 4 other patients demonstrated less dramatic, but also unexpected, responses associated with sildenafil. In view of these findings, WM tumor cells were culture-sorted with sildenafil at pharmacologically achievable levels and apoptosis was demonstrated in tumor cells from all 5 patients. These studies suggest that sildenafil may be an active agent in the treatment of WM.
Vascular rejection in cardiac transplantation: Histologic, immunopathologic, and ultrastructural features.

Although the majority of rejection found in cardiac transplant biopsies is cellular in type, a variety of vascular alterations occur in cardiac biopsies, constituting different forms of rejection that can be recognized using light microscopic and immunopathologic criteria. In this report, pathologic aspects of the vascular alterations associated with vascular and mixed rejection of cardiac allografts are described in detail. Methods and controls used in this report are identical to those previously reported. The histologic, immunopathologic, and ultrastructural findings associated with vascular rejection and other vascular processes in cardiac allografts are discussed. The relationship of these findings to chronic allograft rejection and potential pathogenetic mechanisms of these vascular changes are also detailed.
Drug choices in the treatment of atrial fibrillation

When considering therapy for atrial fibrillation (AF), the dominant issues are rate control, anticoagulation, rhythm control, and treatment of any underlying disorder. Drug choices for rate control include beta-blockers, verapamil and diltiazem, and digitalis as first-line agents, with consideration of other sympatholytics, amiodarone, or nonpharmacologic approaches in resistant cases. Anticoagulation may be accomplished with aspirin or warfarin, with the latter preferred in all older or high-risk patients. Antiarrhythmic drug therapy may be used (1) to produce cardioversion (most effective with ibutilide or class IC agents in recent onset AF); (2) to facilitate electrical conversion (class III agents); (3) to prevent early reversion after cardioversion; (4) to maintain sinus rhythm during chronic therapy; and/or (5) to facilitate conversion of fibrillation to flutter, which may then be amenable to termination or prevention with antitachypacing or ablative techniques. Antiarrhythmic drug selection for AF is guided by efficacy considerations (most drugs are similar), by convenience, cost, and discontinuation considerations; and, most importantly, by safety considerations. When possible, agents with serious organ toxicity potential and proarrhythmic risk should be avoided as first-line choices. In structurally normal hearts, class IC antiarrhythmic drugs are least proarrhythmic and least organ toxic (when considered together). In normal hearts, sotalol, dofetilide, and potentially azimilide also appear to have attractive profiles. Amiodarone has low proarrhythmic risk but can produce bradyarrhythmias and toxicity. In hypertrophied hearts, the risk of torsade de pointes with class III/IA agents is enhanced, whereas in ischemia or conditions with impaired cell contact, whether functionally (as by ischemia) or anatomically (as by fibrosis, infiltration, etc), proarrhythmic risk with class I antiarrhythmic drugs (sustained ventricular fibrillation/flutter) is greatly increased. The class I drugs should be avoided in these circumstances. Additional issues to consider are where to initiate therapy (in- or outpatient), what follow-up protocols to use, and whether to limit therapy to proprietary drugs or to allow generic formulation substitution. Each of these considerations is detailed in this article.
THE CLINICAL PRACTICE OF EMERGENCY MEDICINE

This article provides brief updates, pearls, and pitfalls on aspects of emergency practice that are dealt with routinely, including the application of diagnostic testing in the emergency department, ruling out subarachnoid hemorrhage, and the use of tympanic temperatures. Physician-patient and physician-physician communication skills are addressed. Finally, medicolegal and administrative topics, such as EMTALA, writing admitting orders, treating minors in the emergency department, and blood product therapy in Jehovah's Witnesses are also discussed.
Interpersonal deception. I : Deceivers' reactions to receivers' suspicions and probing

Mutual influence in deception was investigated in a study on the effectiveness of probing as a detection strategy. It was proposed that receivers communicate suspicion in probing questions, causing deceivers to alter their nonverbal presentations and appear more convincing, and that detection when probing is improved by suspicion and familiarity with the source. Interviews were conducted in which the source (a stranger or friend) either told the truth or lied to receivers. Half of the receivers were induced to be suspicious and half probed for additional information. Receivers in the suspicion condition actually encoded less suspicious probes, suggesting that they attempted to deceive sources about their suspicions. However, their nonverbal behavior belied more cognitive activity, perhaps due to increased scrutiny of sources’ communication. By comparison, deception triggered more suspicious probes. Sources accurately perceived suspicion and were more sensitive to suspicion communicated by friends, implyin...
Observations of the diurnal tide from space

This study presents a climatology of mesospheric and lower-thermospheric diurnal tidal winds obtained with the High Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite (UARS). The observations reveal that although tidal structures are present at all times, like the prevailing zonal winds, they exhibit significant semiannual as well as other shorter-term variations in amplitude. Results are presented for a period extending over more than one year from November 1991 to July 1993. The 1,1 diurnal tidal amplitude of the meridional component, characterized by the value at an altitude of 90 km and a latitude of 22 deg, ranges from a minimum at solstice of less than 20 m per sec to an equinox maximum of over 70 m per sec. The vertical wavelength and phase of the tide show only slight variations throughout the year, with a suggestion of semiannual variations in both.
Zur Phagenkonversion von Clostridium novyi Typ A

Abstract Clostridium novyi type A, the cause of gas gangrene in man and animal, produces four main toxic components (alpha, gamma, delta, and epsilon). The alpha toxin is a necrotizing toxin produced in lethal amounts by strains of type A. This lethal toxin induces a characteristic subcutaneous colorless gelatineous edema when guinea pigs are infected with C. novyi type A. In this paper we report further evidence on the relationship of bacteriophages to the production of alpha toxin by C. novyi type A. The results showed that five phage-sensitive bacterial strains that did not produce alpha toxin could be isolated from alpha toxin producing strains. These nontoxigenic strains could be infected with specific bacteriophages isolated from the different toxigenic strains of C. novyi type A and converted to alpha toxin production. The toxigenicity of these converted strains depended upon the continued participation of specific bacteriophages. These bacteriophages were shown to be very unstable in culture supernatant fluids.
Increased Expression of β‐Amyloid Protein Precursor and Microtubule‐Associated Protein τ During the Differentiation of Murine Embryonal Carcinoma Cells

Expression of the genes encoding the beta/A4 amyloid protein precursor (APP) and microtubule-associated protein tau was studied in an embryonal carcinoma cell line (P19) that differentiates in vitro into cholinergic neurons after treatment with retinoic acid. Expression of APP increased 34- (mRNA) and 50-fold (protein) during neuronal differentiation; APP-695 accounted for most of this increase. These remarkable increases in APP expression coincided with a proliferation of neuronal processes and with an increase in content of tau mRNA. Moreover, subsequent decreases in the levels of APP and tau mRNA coincided with the onset of the degeneration of the neuronal processes. Immunocytochemical staining suggested that greater than 85% of the P19-derived neurons are cholinergic and that APP is present in the neuronal processes and cell bodies. These results suggest that APP may play an important role in construction of neuronal networks and neuronal differentiation and also indicate that this embryonal carcinoma cell line provides an ideal model system to investigate biological functions of APP and the roles of APP and tau protein in development of Alzheimer's disease in cholinergic neurons.
Characterization of the binding of transforming growth factor-beta 1, -beta 2, and -beta 3 to recombinant beta 1-latency-associated peptide.

Preprotransforming growth factor-beta 1 (TGF beta 1) is a 390-amino acid precursor polypeptide that undergoes a number of processing steps to yield mature TGF beta 1 (amino acid residues 279-390) and a pro portion (residues 30-278) termed beta 1-latency-associated peptide (beta 1LAP). The dimeric form of beta 1LAP has been shown to associate noncovalently with the mature growth factor, resulting in inactivation of biological activity. To further characterize this interaction, the mature TGF beta 1 was radioiodinated and used to determine dissociation constants. A cross-linking method using the bifunctional covalent cross-linker bis-(sulfosuccinimidyl)suberate was found to be the best approach for measuring the amount of bound growth factor. The efficiency of cross-linking was constant within each experiment and varied between 45-55%. Saturation plots and their associated Scatchard analyses indicate apparent Kd values between 1.1-1.8 nM. Competition of TGF beta 1 binding to beta 1LAP by TGF beta 2 and TGF ...
The sorting direct method for stochastic simulation of biochemical systems with varying reaction execution behavior

A key to advancing the understanding of molecular biology in the post-genomic age is the development of accurate predictive models for genetic regulation, protein interaction, metabolism, and other biochemical processes. To facilitate model development, simulation algorithms must provide an accurate representation of the system, while performing the simulation in a reasonable amount of time. Gillespie's stochastic simulation algorithm (SSA) accurately depicts spatially homogeneous models with small populations of chemical species and properly represents noise, but it is often abandoned when modeling larger systems because of its computational complexity. In this work, we examine the performance of different versions of the SSA when applied to several biochemical models. Through our analysis, we discover that transient changes in reaction execution frequencies, which are typical of biochemical models with gene induction and repression, can dramatically affect simulator performance. To account for these shifts, we propose a new algorithm called the sorting direct method that maintains a loosely sorted order of the reactions as the simulation executes. Our measurements show that the sorting direct method performs favorably when compared to other well-known exact stochastic simulation algorithms.
Risk Stratification of Nonvariceal UGI Hemorrhage for the Practicing Endoscopist

It is important for practicing endoscopists and clinicians to understand the principles of risk stratification in patients with acute, nonvariceal UGI hemorrhage. Its intent is to stratify or triage individual patients according to severity of disease and risk of adverse clinical outcome. Patients can then receive the most appropriate care according to the severity of their illness. Risk stratification permits the early triage of patients into low and higher risk groups. Low-risk patients can be offered outpatient management or an abbreviated hospital stay. Patients at higher risk can be quickly identified so that they can receive appropriate management that is tailored to the severity of their disease. Risk stratification is an active, ongoing process that continues throughout the patients' clinical encounter. Although early endoscopy is a key component of the process, it is not essential. There are three main stages in risk stratification: (1) clinical presentation, (2) endoscopy, and (3) postendoscopic therapy or postendoscopy. Published evidence would indicate that risk stratification is important and can lead to more cost-effective delivery of health care when clinicians understand and act on it.
How Information School Students Helped Local Displaced Homemakers Become Entrepreneurs Through Technology: The BOOST Initiative

Library and Information Science students, along with students from other programs in the School of Information Studies (iSchool) at Syracuse University, developed and implemented a technology curriculum to train displaced homemakers. The Chancellor's Scholarship in Action initiative at Syracuse University was the catalyst for forming a partnership with the Women's Opportunity Center that served the local community. With funding from the Kauffman Foundation, an Enitiative project called BOOST (Bolstering Original Opportunity and Self through Technology) began. The initiative was to provide technology training and entrepreneurial opportunities to women within the Syracuse community. The intent was to design a program that could be delivered in the local community and easily replicated for deployment in libraries and community centers nationally. Additionally, the students involved in the project gained valuable insights into the teaching and learning process, project management and became very engaged in th...
Reversals of national fortune, and social science methodologies

Among non-European regions colonized by Europeans, regions that were relatively richer five centuries ago (like Mexico, Peru, and India) tend to be poorer today, while regions that originally were relatively poorer (like the United States, Chile, and Australia) tend now to be richer. Acemoglu, Johnson, and Robinson (abbreviated AJR) established the generality of this reversal of fortune. Chanda, Cook, and Putterman (abbreviated CCP) have now reanalyzed it, taking as a unit of analysis populations rather than geographic regions. That is, India's population was Indian 500 y ago and is still overwhelmingly Indian today, whereas the United States' population was Native American 500 years ago but is overwhelmingly Old World (especially European) today. Reversals of fortune disappeared when CCP analyzed populations rather than geographic regions: for instance, the geographic region of the modern United States has become relatively richer since AD 1500, but the predominantly European population now occupying the United States was already relatively rich in AD 1500. Evidently, European colonists carried ingredients of wealth with them. I discuss the biological and cultural baggage transported by European immigrants and associated with wealth. Among that baggage, AJR emphasize institutions, CCP emphasize social capital, and I identify many different elements only loosely coupled to each other. This paper discusses the problem, especially acute in the social sciences, of “operationalizing” intuitive concepts (such as mass, temperature, wealth, and innovation) so that they can be measured. Basic concepts tend to be harder to define, operationalize, and measure in the social sciences than in the laboratory sciences.
cDNA expression arrays reveal incomplete reversal of age-related changes in gene expression by calorie restriction

Calorie restriction (CR) extends life span and retards many age-related cellular and molecular changes in laboratory rodents. However, neither the breadth of its effects, its underlying mechanisms, nor the limits of its action is fully understood. Expression levels of 588 genes in livers from 3- and 24-month-old ad libitum-fed (AL), and 24-month-old CR (60% of AL intake) male C57BL/6J mice (four per group) were measured. Six genes met the statistical criteria for differential expression in old AL compared to young AL mice. Only one of these age-related changes was attenuated by CR. Four additional gene products, that did not change with age in AL mice, were differentially expressed in old CR compared to old AL mice. Northern and RT-PCR analyses confirmed differential expression of four of the six candidate genes identified by the array results. Many of the identified genes have not previously been reported to be affected by CR or aging. Some of the age-related changes in gene expression are consistent with an increased vulnerability of the aged liver to carcinogenic or other insults, with only partial protection against insult by CR. Incomplete reversal by CR of age-related changes in gene expression provides a potentially important path for probing the limits of CR action. These results also show the importance of independent confirmation in expression array profiling of age-related changes in gene expression.
Win Some, Lose Some: The Effect of Chronic Losses on Decision Making Under Risk

Losses, including those that are chronic in nature, are a fact of life. The research reported here was designed to examine, using a controlled experiment, the effect of chronic losses in a given contextual domain on subsequent decisions with uncertain outcomes that take place in the same and in unrelated domains. Randomly selected adult subjects who took part in the experiment were randomly assigned to one of three treatment groups: One group, chronic losers, was exposed to chronic financial losses as part of a controlled, multi‐round gambling simulation. Groups two and three were exposed to chronic wins and random outcomes, respectively, as part of the same gambling simulation. Results from the experiment revealed that chronic losses, in contrast to random outcomes and chronic wins, had clear effects on decision making in the domain where the initial losses were incurred. Subjects who were exposed to the chronic loss induction demonstrated a significantly higher level of risk aversion when compared with ...
Organizational climate as a moderator of safety knowledge–safety performance relationships

Using training history data and supervisory ratings of 133 hazardous waste workers' safety performance collected within two organizations in the U.S. nuclear waste industry, this study examined organizational climate for the transfer of safety training as a moderator of relationships between safety knowledge and safety performance. The trend in the results was consistent with the hypothesis that these relationships would be stronger in the less restrictive (more supportive) organizational climate. The implications of these findings for promoting safe work behaviors through the creation of a positive and strategically focused organizational climate for the transfer of safety training are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Choice ball: A response interface for two-choice psychometric discrimination in head-fixed mice

The mouse is an important model system for investigating the neural circuits mediating behavior. Because of advances in imaging and optogenetic methods, head-fixed mouse preparations provide an unparalleled opportunity to observe and control neural circuits. To investigate how neural circuits produce behavior, these methods need to be paired with equally well-controlled and monitored behavioral paradigms. Here, we introduce the choice ball, a response device that enables two-alternative forced-choice (2AFC) tasks in head-fixed mice based on the readout of lateral paw movements. We demonstrate the advantages of the choice ball by training mice in the random-click task, a two-choice auditory discrimination behavior. For each trial, mice listened to binaural streams of Poisson-distributed clicks and were required to roll the choice ball laterally toward the side with the greater click rate. In this assay, mice performed hundreds of trials per session with accuracy ranging from 95% for easy stimuli (large interaural click-rate contrast) to near chance level for low-contrast stimuli. We also show, using the record of individual paw strokes, that mice often reverse decisions they have already initiated and that decision reversals correlate with improved performance. The choice ball enables head-fixed 2AFC paradigms, facilitating the circuit-level analysis of sensory processing, decision making, and motor control in mice.
Biodynamic 3D Imaging for Personalized Cancer Care

Tumor heterogeneity and differential drug response in 3D tissue is a major obstacle for survival of cancer patients. Biodynamic 3D imaging provides personalized therapy assessment by testing heterogeneous response of tumor biopsies to anti-cancer drugs.
Intracortical termination of the retino-geniculo-striate pathway studied with transsynaptic tracer (wheat germ agglutinin-horseradish peroxidase) and cytochrome oxidase staining in the macaque monkey

The tracer, wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP), was used as a transneuronal marker in the macaque monkey to study retino-geniculo-striate pathway terminals in area 17. Concomitantly, we stained matching sections for metabolic capacity using the cytochrome oxidase staining technique. Terminal labeling by WGA-HRP and cytochrome oxidase activity staining revealed duplicate patterns in layers II and III, IVA, IVC alpha, IVC beta, and VI. The absence of WGA-HRP-labeled neuronal cell bodies in area 17 supports the conclusion that WGA-HRP is a transsynaptic marker in the macaque visual pathways.
Subthreshold antikaon production in nucleus-nucleus collisions

Abstract Antikaon production in nucleus-nucleus collisions at energies below the threshold for its production from the nucleon-nucleon interaction in free space is studied in the relativistic transport model. We include the in-medium self-energies of kaon and antikaon determined from either the mean-field approximation to the chiral Lagrangian or the empirical effective scattering lengths for the kaon-nucleon and the antikaon-nucleon interaction. Also, the final-state interactions of antikaons with nucleons through both elastic scattering and absorption are explicitly treated in the study. Our results indicate that an attractive scalar potential for kaon and antikaon is needed to explain quantitatively the experimental data from the Ni+Ni collision at 1.85 GeV/nucleon. To see more clearly the effect of the attractive scalar potential, we suggest that experiments at lower incident energies be carried out.
Effects of naphthalene on microbial activity and nitrogen pools in soil-litter microcosms

Abstract Naphthalene effects on microbial respiration, numbers of bacteria and fungi, and litter and soil nitrogen pools were investigated in litter-soil microcosms containing microbes but no mesofauna. Naphthalene was applied three times during the 56 day study. Total respiration was unaffected by the first application of naphthalene, but increased upon subsequent applications. Bacteria and fungi in the litter and soil were quantified separately at the end of the study. Numbers of bacteria were significantly higher in both litter and soil of naphthalene-treated microcosms. Lengths of total and FDA-active fungal hyphae in the litter and soil, respectively, were significantly lower in the naphthalene treatment. Mass loss of litter was not affected. However, both the final concentration and absolute amount of N in the litter were reduced by naphthalene, as was soil extractable NH 4 -N and NO 3 - + NO 2 -N. These results suggest that naphthalene may directly affect microbial populations and activity and alter nitrogen dynamics and that caution should be used in interpreting results of field studies using naphthalene to exclude microarthropods.
Refined Solution Structures of the Escherichia coli trp Holo- and Aporepressor

Abstract The solution structures of the trp -repressor from Escherichia coli in both the liganded (holo-) and unliganded (apo-) form, have been refined by restrained molecular dynamics with simulated annealing using the program XPLOR and additional experimental constraints. The ensemble of refined holorepressor structures have a root-mean-square deviation (r.m.s.d.) of 0·8 A relative to the average structure for the backbone of the dimer core (helices A, B, C, A′, B′, C′) and 2·5 A for the helix-turn DNA-binding domain (helices D and E). The corresponding values for the aporepressor are 0·9 A for the backbone of the ABC-dimer core and 3·2 A for the DE helix-turn-helix. The r.m.s.d. of the average structures from the corresponding crystal structures are 2·3 A for the holorepressor ABC core and 4·2 A for its DE region; 2·3 A for the aporepressor core and 5·5 A for its DE region. The relative disorder of the DNA-binding domain is reflected in a number of experimental parameters including substantially more rapid backbone proton exchange rates, exchange-limited relaxation times and crystallographic B -factors. The stabilizing effect of the l -Trp ligand is evident in these measurements, as it is in the higher precision of the holorepressor structure.
Understanding the PRBS signal as an optimum input signal in the wavelet-correlation method of system identification using multiresolution analysis

This paper will focus on the relationship between the pseudo-random binary sequence (PRBS) signal and the dyadic lattice. A method for estimating the PRBS function by a series of Haar wavelets is derived and explained. Relating the PRBS signal to the Haar wavelet is advantageous because the Haar wavelet forms an orthonormal wavelet basis. Multiresolution analysis is used to write the PRBS signal as a finite series of Haar wavelets, and the dyadic period of the PRBS signal is exploited to make this task easier. The PRBS signal and dyadic lattice are shown to be complimentary choices for the wavelet-correlation (W-C) method.
Roadside range sensors for intersection decision support

We are developing an "intersection decision support" (IDS) system to assist drivers with decision-making at unsignalized rural intersections. When deployed, the system provides to a driver stopped at a minor road, information related to the safety of entering or crossing the mainline road traffic stream. The system uses surveillance sensors alongside the major road to determine the state of the intersection, and this state information is used to determine whether the gaps that exist are unsafe, thereby triggering a warning to the stopped driver not to initiate the desired maneuver. Low cost automotive radar forms the basis of the surveillance system. This paper presents a performance evaluation of an Eaton-Vorad EVT-300 radar used as a fixed-base sensor for an IDS system. This evaluation documents the sensor's coverage of the lanes, its lane classification ability and its accuracy at tracking speed as a function of the unit's orientation to the road. High accuracy (5 cm) DGPS is used to validate all radar measurements.
Observation of autoionizing states of beryllium by resonance-ionization mass spectrometry

We have made the first reported observations of the Be 2p21S state, and of high-lying members of the Rydberg series 2pnd1P° (n⩽16), by multiphoton resonance-ionization mass spectrometry (RIMS). The energy of the 1S state is compared with a number of theoretical predictions, which differ from one another over a range of about 0.75 eV. Good agreement is found when corrections are made for intershell electron correlations. These results show that precision spectroscopy can be performed by RIMS with samples of a few hundred atoms and that direct multiphoton excitation of autoionizing states may be a useful new addition to the existing catalog of resonance-ionization schemes.
Closed-loop seizure prediction and prevention in rats with kainate-induced seizures

Many studies have shown that continuous or intermittent electrical stimulation of the brain can reduce or prevent the occurrence of epileptic seizures in humans and animal models. However, there have been relatively few studies that assess the effects of stimulation delivered just prior to seizure onset. Here we use a kainate-induced seizure model in the rat to test a closed-loop seizure prediction and prevention system. An algorithm was created that extracts a measure from the activity of populations of single neurons, and predicts the probability of a seizure in real time. Once a seizure is predicted, high frequency current pulses are applied to the hippocampus to attempt to inhibit the network and prevent the seizure from occurring. Results show that although not every seizure could be prevented, the majority of stimulation trials delayed or prevented a pending seizure. These results suggest that a closed-loop seizure prediction algorithm based on neuronal activity coupled with intracranial stimulation may be more effective than random stimulation at preventing the onset of seizures.
Nongovernmental Organizations and the Option Value of Donated Land

Nongovernmental organizations frequently receive donations of land that have unknown characteristics. This paper presents an analytical model of the option to preserve such land. The nongovernmental organizations' option value arises from the option to preserve or sell the land to generate funds for other preservation projects. We show that die preservation option is equivalent to an option that allows the nongovernmental organization to choose between he maximum of the market value of the land and the preservation value of the land. From the resulting closed from solution of the option to preserve, we perform comparative statics showing how the relevant factors (preservation value of the land, the development value of the land, the length of the that the option is available, and the uncertainty surrounding the relative values of preservation and development) influence the value of the preservation option. In addition, to the basic model, we present three model modifications. The first examines the effects of costly preservation and costly nonpreservation. In the second extension, we examine the effects of freeriding modeled by a continuous variable. In the final modification, we relax the assumption of the fixed survey period and show the optimal development date.
Comparative effect of flunarizine in two animal models of stroke.

SUMMARY 1. A common ‘stroke model’, the rat middle cerebral artery occlusion preparation, was used to compare photocoagulation with mechanical occlusion. 2. Areas of cerebral infarction and of vascular leakage were compared using these two methods. The general pattern of damage was similar, with central infarcted areas surrounded by larger vascular leakage areas. 3. The two models differed in the extent of their vascular leakage areas and in their response to the cerebroprotective agent flunarizine. 4. We conclude that the two models are not equivalent, probably because they do not damage the vascular endothelium to the same degree.
Blood Pressure and Risk of Death from External Causes among Men Screened for the Multiple Risk Factor Intervention Trial

A few epidemiologic studies have shown an increased risk of death from external causes among men with hypertension. Previous studies were limited by small numbers of events, however, and none assessed the association of blood pressure with specific types of ‘‘accidental’’ death. The authors examined data obtained from baseline interviews and 25 years of mortality follow-up (1973� 1999) for 347,978 men screened for the US Multiple Risk Factor Intervention Trial. Proportional hazards regression analyses were used to quantify associations of blood pressure with all external causes of death and individual causes. There were 3,910 deaths from external causes, including 2,313 unintentional injuries, 1,248 suicides, and 349 homicides. Compared with those for men whose blood pressure status was ‘‘normal’’ according to the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, the multivariate-adjusted hazard ratios and 95% confidence intervals for death from external causes among men with prehypertension, stage 1 hypertension, and stage 2 hypertension were 0.91 (95% confidence interval (CI): 0.83, 1.00), 1.06 (95% CI: 0.96, 1.16), and 1.44 (95% CI: 1.28, 1.62), respectively. Men with stage 2 hypertension had multivariate-adjusted hazard ratios of 1.90 for falls (95% CI: 1.32, 2.74), 1.45 for motor vehicle injuries (95% CI: 1.14, 1.85), 1.33 for other ‘‘accidents’’ (95% CI: 1.06, 1.66), 1.40 for suicide (95% CI: 1.13, 1.73), and 1.35 for homicide (95% CI: 0.92, 1.97). For men, hypertension may signal an increased risk of death from external causes. accidental falls; accidents; epidemiologic studies; hypertension; mortality
Rb-Sr Ages of Diagenesis of Mg-rich Clay in Permian Sediments, Palo Duro Basin, Texas Panhandle, U.S.A.

ABSTRACT Mid- to upper Permian sedimentary rocks in the shallow (< 3 km), intracratonic Palo Duro Basin, Texas Panhandle, occur in multicyclic carbonate-evaporite-redbed sequences, interpreted to be hypersaline shelf depositional assemblages. Certain marker horizons can be traced continuously over the entire basin. Clay minerals include distinctive varieties of Mg-rich smectite, chlorite, or mixed-layer species resulting from diagenesis in an evaporitic environment. Discrete particle-size fractions of clay were separated from core recovered from the Tubb (Leonardian), San Andres Unit #4 (lower Guadalupian), upper Seven Rivers (upper Guadalupian), and Salado-Tansill (Guadalupian-Ochoan) Formations to determine the times of mineral genesis. Rb-Sr isotopic data, for aliquots of a clay sample that has been leached by diverse ion exchange reagents, plot as a linear array in a Rb-Sr isochron diagram. For ultra-fine clay (< 0.05 µm), interpreted to be diagenetic, the slope of the data array corresponds to the time of diagenesis. Ages of clay diagenesis in the four sampled stratigraphic units agree generally with ages of deposition according to the geologic time scale, signifying that diagenesis was penecontemporaneous with deposition. Analyses of coarser clay fractions (0.2-0.5 µm and 2-4 µm) indicate the presence of a detrital component. In most instances, initial 87Sr/86Sr in diagenetic clay is higher than the Sr isotope ratio measured directly in associated anhydrite. Introduction of radiogenic Sr from occasional stream influx or from concurrent diagenetic dissolution of silicate detritus could have elevated 87Sr/86Sr in the ambient brine that mediated clay diagenesis.
Using geographic information systems (GIS) for UAV landings and UGV navigation

Unmanned air and ground platforms are not currently designed to process contextual information (e.g., land use, building types and time of day) to assist in landing and navigation. Instead, a human operator often provides manually-gathered and synthesized contextual input through control commands. This paper describes research that explores the integration of geographic information system (GIS) data with sensor data to enable (1) unmanned aerial vehicles (UAV) to locate safe emergency landing locations without operator intervention, and (2) unmanned ground vehicles (UGV) to incorporate contextual GIS information for navigation. Informal evaluation of the system revealed the potential to impact navigation and emergency landings through the additional contextual information provided.
Spontaneous Classification of Foods by Elementary School-Aged Children

This study examined children's conceptions about nutrients and the dimensions underlying their classifications of foods into groups. Children aged 5 to 11 (59 girls and 56 boys) placed 71 foods into groups by whatever criteria they wished. The bases of these clasifications were recorded, as were the children's answers to questions about nutrients and their responses in tasks assessing cognitive developmental level. A cluster analysis of the classification data yielded four major groups. However, these groups differed in several respects from the Basic Four food groups generally taught in nutrition education, in ways including the presence of a sweets group. Multidimensional scaling analysis revealed common underlying dimensions of sweet versus nonsweet foods and meal entrees versus drinks and breakfast foods, suggesting that perceptual, functional, and physical properties of foods influenced food classifications by children regardless of cognitive developmental level. However, only "concrete operational" ...
Mechanism and rate of sugar uptake by Acremonium typhinum, an endophytic fungus infecting Festuca rubra: evidence for presence of a cell wall invertase in endophytic fungi

Fungal endophytes of the genus Acremonium infect many grass species. They exist in the intercel? lular spaces of the aerial plant parts, most abundantly in the leaf sheaths. They therefore must obtain all of their nutrients from the apoplastic spaces in the plant. This report is the first comprehensive, biochemically based study of sugar uptake by Acremonium spp. The endophytes (Acremonium typhinum) were isolated from Festuca rubra plants and were grown in culture. Indi? vidual colonies were incubated in the presence of (U- 14C)radiolabeled glucose, fructose, or sucrose for 20 minutes and the uptake quantified by scintillation counting. The uptake rates for all three sugars were biphasic, indicating two distinct mechanisms of trans- port. At low sugar concentrations (below 10 mM) the uptake was saturable and had the characteristics of a carrier-mediated mechanism. At high sugar concen? trations (10-100 mM) the uptake was linear suggesting diffusion as the predominant mechanism of uptake. From competition experiments (uptake of labeled sug? ar in the presence of a different unlabeled sugar) it appeared that there were separate carriers for glucose and fructose. Two mechanisms for sucrose uptake were detected, a sucrose carrier and hexose uptake as a result of cell wall invertase. Cell wall invertase activity of the fungal isolates was inducible by growing the fungi on sucrose containing media.
Configurational effects on polystyrene rejection from microporous membranes

Dilute solutions of polystyrene in chloroform were filtered through track-etched mica membranes. The pores of each membrane were smaller than the mean unperturbed dimension of the polymer molecules. Three configurations of polystyrene were used: linear, comb-branched, and star-branched. The data for the linear polystyrenes show that the reflection coefficient σ decreases with solvent flow rate per pore q in a manner independent of molecular weight. At low flow rates the rejection is quantitatively described by 1 − σ ∼ q1.69. Comparisons among the three configurations show that as the extent of branching increases, σ increases at given solvent flow rate. It is concluded that filtration studies with well-defined porous membranes can provide a relative measure of deformability among various configurations of polymeric species.