cssi/SciSciGPT-SciSciNet huggingface dataset:
Perceptions of Education during COVID-19 among Agronomy, Soil, and Environmental Science Students

The COVID-19 pandemic required changes in college course delivery, which may influence student perceptions of their education. We examined those perceptions among Students of Agronomy, Soil, and Environmental Sciences (SASES). The goals were to determine how changes in education during the COVID-19 pandemic (a) changed student perceptions of online education, (b) shifted student comfort with online education and communication, and (c) highlighted issues limiting student success. A link to an online survey was sent to SASES members in late 2020 resulting in 31 responses. Course format shifted from mostly face-to-face delivery to synchronous and asynchronous online delivery following the COVID-19 shutdown. Students perceived decreased instructor effort and increased student effort. Nearly all students had access to devices. However, access to fast, reliable internet was a common issue. A small percentage of students were more likely to take online courses after the pandemic, yet a majority were now more comfortable taking online classes and using virtual meeting software. Student concern for COVID-19 was low. However, most reported wearing masks in buildings and on campus. Students reported increases and decreases in hours worked, with both changes resulting in perceived positive and negative academic impacts. These results should be considered by instructors and administrators planning instruction format changes during and after the COVID-19 pandemic.
Explaining Patronage Distribution in One-Party Regimes: Evidence from China’s Public Employment

Public employment is seldom created for the sole purpose of public service. In democracies and electoral autocracies, public employment is typically a source of political patronage. What then explains the distribution of public employment in one-party systems, where electoral pressures are absent? This paper identifies the determinants of public employment distribution in China, through which I develop a general theory of patronage distribution in one-party regimes. I argue that the distribution of patronage goods in the absence of electoral institutions operate on two levels. At the macro level, patronage goods like public jobs are allocated by central decision-makers to ease ethnic tensions (or more generally to strengthen national unity); and at the micro level, public jobs are created by individual leaders to build personal political networks or dispensed as nepotistic goods. My analysis of an original public employment dataset across China’s provinces from 1997 to 2007 finds support for these propositions. All things equal, we find that provinces designated as autonomous regions and provinces with a new leader in office experience a significantly higher rate of public employment growth than other provinces. These results shed new light on the dynamics of redistributive politics in one-party regimes.
Lactobacillus rhamnosus GG Orchestrates an Antitumor Immune Response.

ABSTRACT Background and Aims In colorectal cancer, about 95% of patients are refractory to immunotherapy due to low anti-tumor immune responses. Therefore, these is an exigent need to develop treatments that increase anti-tumor immune responses and decrease tumor burden to enhance immunotherapy. Methods The gut microbiome has been described as a master modulator of immune responses. We administered the human commensal, Lactobacillus rhamnosus GG (LGG) to mice and characterized the changes in the gut immune landscape. Because the presence of lactobacilli in the gut microbiome has been linked with decreased tumor burden and anti-tumor immune responses, we also supplemented LGG to a genetic and a chemical model of murine intestinal cancer. For clinical relevance, we therapeutically administered LGG after tumors had formed. We also tested for the requirement of CD8 T-cells in LGG-mediated modulation of gut tumor burden. Results We detected elevated colonic CD8 T-cell responses specifically in LGG supplemented mice. The CD8 T-cell induction was dependent on dendritic cell activation mediated via Toll-like receptor-2 (TLR2), thereby describing a novel mechanism where a member of the human microbiome induces an intestinal CD8 T-cell response. We also show that LGG decreased tumor burden in the murine gut cancer models by a CD8 T-cell-dependent manner. Conclusions These data support the potential use of LGG to augment anti-tumor immune responses in colorectal cancer patients and ultimately for increasing the breadth and efficacy of immunotherapy.
MR characteristics of mucinous tubular and spindle cell carcinoma (MTSCC) of the kidney: comparison with clear cell and papillary subtypes of renal cell carcinoma.

To describe MR features of mucinous tubular spindle cell carcinoma (MTSCC) of the kidney that may help differentiate from clear cell renal cell carcinoma (ccRCC) and papillary RCC (pRCC). 15 MTSCCs were retrospectively evaluated by MR with T2-weighted image without fat suppression (n = 15) and dynamic contrast-enhanced (DCE), fat-suppressed T1-weighted GRE (n = 11). Size-matched ccRCC (n = 30) and pRCC (n = 30) were evaluated as control. T2 ratio was calculated as the signal intensity (SI) ratio of the lesion to the renal cortex on T2W images. Enhancement ratio (ER) was calculated as (SIpost − SIpre)/(SIpre), where SIpre (SIpost) is the SI of the entire lesion on each phase of DCE images. Early nodular enhancement was subjectively evaluated in MTSCC. T2 ratio and ER were compared using the Mann–Whitney U test with Bonferroni correction. The mean value of T2 ratio was highest in ccRCC (1.24), followed by MTSCC (1.02), and pRCC (0.84). Difference of T2 ratio was significant between ccRCC and pRCC (p < 0.001), but not between MTSCC and ccRCC (p = 0.4) or between MTSCC and pRCC (p = 0.2). The mean ER of MTSCC, ccRCC and pRCC were 1.33, 1.53 and 0.38 in corticomedullary phase (CMP), 1.60, 1.61 and 0.69 in nephrographic phase (NGP) and 1.79, 1.35 and 0.77 in excretory phase (EP), respectively. ERs were significantly different between MTSCC and pRCC in CMP (p = 0.01), NGP (p = 0.003), and EP (p = 0.002). Early nodular enhancement was observed in 4/11 MTSCC (36%), 17/30 ccRCC (57%), and 2/30 pRCC (7%). MTSCC has distinct MR features that can help differentiate from ccRCC and pRCC. MTSCC enhances more avidly compared to pRCC and shows gradual progressive enhancement.
RKRD: Runtime Kernel Rootkit Detection

In this paper we address the problem of protecting computer systems against stealth malware. The problem is important because the number of known types of stealth malware increases exponentially. Existing approaches have some advantages for ensuring system integrity but sophisticated techniques utilized by stealthy malware can thwart them. We propose Runtime Kernel Rootkit Detection (RKRD), a hardware-based, event-driven, secure and inclusionary approach to kernel integrity that addresses some of the limitations of the state of the art. Our solution is based on the principles of using virtualization hardware for isolation, verifying signatures coming from trusted code as opposed to malware for scalability and performing system checks driven by events. Our RKRD implementation is guided by our goals of strong isolation, no modifications to target guest OS kernels, easy deployment, minimal infra-structure impact, and minimal performance overhead. We developed a system prototype and conducted a number of experiments which show that the per-formance impact of our solution is negligible.
Fumarate reductase mutants of Escherichia coli that lack covalently bound flavin.

Abstract Menaquinol-fumarate oxidoreductase of Escherichia coli is a four-subunit membrane-bound complex that catalyzes the final step in anaerobic respiration when fumarate is the terminal electron acceptor. The catalytic domain of fumarate reductase consists of the FrdA subunit, which contains the active site, and a FAD prosthetic group covalently attached to His44, plus the FrdB subunit which contains at least two of the three nonidentical iron-sulfur clusters of the enzyme. To examine the role of covalently bound FAD in enzyme activity and electron transfer during anaerobic cell growth, site-directed mutagenesis was used to alter His44 of the FrdA subunit to a Ser, Cys, or Tyr residue. The resulting mutant enzyme complexes that were synthesized associated normally with the cytoplasmic membrane, but had decreased ability (greater than 70%) to reduce fumarate with reduced benzyl viologen, an artificial electron donor of low redox potential (Em = -359 mV; Clark, W. M. (1972) Oxidation-Reduction Potentials of Organic Systems, Robert E. Kreiger Publishing Co., Melbourne, FL). Even lower activities were measured when the higher potential, natural electron donor menaquinol was used, which, however, correlated with the slower growth rates of the different mutant complexes. In contrast to the normal enzyme, the mutant enzyme complexes were unable to oxidize succinate. Substitution of Arg for His44 produced a totally inactive enzyme complex that permitted no cell growth on nonfermentable substrates with fumarate as electron acceptor. All four mutant complexes contained noncovalently bound FAD in stoichiometric amounts. These data indicate a unique role of the 8 alpha-[N(3)-histidyl] FAD linkage in enzyme activity, by raising the redox potential of free FAD to permit reduction by both menaquinol and succinate.
Exclusion from Income of Compensation for Services and Pooling of Labor Occurring in a Noncommercial Setting

Compensation for services, regardless of the form, constitutes income to the recipient. Consequently, the exchange of services by two individuals is treated as income to each. However, there are numerous examples of an exchange of services that the IRS has never sought to tax. The most common example is an exchange of services by a married couple who divide the household chores between them. The focus of this article is to propose a principled reason for not taxing those exchanges and to explore the limits of that exclusion. The author contends that the income tax operates exclusively on commercial transactions, and so income derived from a noncommercial activity is not taxable. The article explores what types of activities can be classified as noncommercial for this purpose. As a corollary to the proposed noncommercial rule, the article contends that the income tax does not apply to individuals who pool their labor to obtain a common goal. The resulting exchange of services are not taxable. The article considers the question of how broadly a common goal can be defined for this purpose. The article examines several specific activities in which services are exchanged and which should not be taxable. Specifically, among others the article examines: baby sitting barter clubs, cooperative nursery schools, and home schooling.
Design of Discrete Robust Controller by QFT using PCT-Approach

A pseudo-continuous time (PCT) approach to Quantitative Feedback Theory (QFT) design of discrete robust controllers for highly coupled nonlinear plants was developed and experimentally evaluated on a robotic manipulator [2]. The new method provides a straightforward extension of analog QFT techniques to highly coupled nonlinear plants without degrading the robustness of the resulting QFT controller. A detailed description of the design technique and a sample appliction are presented.
Optimal use of sentinel lymph node biopsy versus axillary lymph node dissection in patients with breast carcinoma: a decision analysis.

BACKGROUND There are no data available from randomized controlled trials that compare the efficacy of sentinel lymph node (SLN) biopsy with Level I/II axillary lymph node dissection (ALND) in patients with breast carcinoma. We performed a formal decision analysis to determine whether SLN biopsy is appropriate, compared with ALND, for patients with T1, T2, and T3 tumors and to quantify the relative value of these two procedures in the management of patients with breast carcinoma. METHODS All clinically relevant outcomes were modeled for both SLN biopsy and ALND. The probabilities of complications and outcomes were derived using data from the University of Louisville Breast Cancer Sentinel Lymph Node Study and from extensive review of previous studies. Utilities were assigned by the authors, incorporating values from the literature whenever possible. RESULTS The expected utility of SLN biopsy was higher than the expected utility for ALND for T1 and T2 tumors that were 4.0 cm or smaller. There was no clear preference for either procedure with tumors that were larger than 4.0 cm. The T1 and T2 results were robust to sensitivity analysis. CONCLUSIONS The results of this decision analysis suggest that SLN biopsy is preferred over ALND for patients with breast tumors that are 4.0 cm or smaller. Patients should be aware of the potential for false-negative results in SLN biopsy, but this risk is outweighed by the decreased morbidity associated with the procedure itself. Cancer 2002;95:478–87. © 2002 American Cancer Society. DOI 10.1002/cncr.10696
Ordered assembly of nucleoprotein structures at the bacteriophage lambda replication origin during the initiation of DNA replication.

Abstract Replication of the chromosome of bacteriophage lambda depends on the cooperative action of two phage-coded proteins and seven replication and heat shock proteins from its Escherichia coli host. As previously described, the first stage in this process is the binding of multiple copies of the lambda O initiator to the lambda replication origin (ori lambda) to form the nucleosomelike O-some. The O-some serves to localize subsequent protein-protein and protein-DNA interactions involved in the initiation of lambda DNA replication to ori lambda. To study these interactions, we have developed a sensitive immunoblotting protocol that permits the protein constituents of complex nucleoprotein structures to be identified. Using this approach, we have defined a series of sequential protein assembly and protein disassembly events that occur at ori lambda during the initiation of lambda DNA replication. A second-stage ori lambda.O (lambda O protein).P (lambda P protein).DnaB nucleoprotein structure is formed when O, P, and E. coli DnaB helicase are incubated with ori lambda DNA. In a third-stage reaction the E. coli DnaJ heat shock protein specifically binds to the second-stage structure to form an ori lambda.O.P.DnaB.DnaJ complex. Each of the nucleoprotein structures formed in the first three stages was isolated and shown to be a physiological intermediate in the initiation of lambda DNA replication. The E. coli DnaK heat shock protein can bind to any of these early stage nucleoprotein structures, and in a fourth-stage reaction a complete ori lambda.O.P.DnaB.DnaJ.DnaK initiation complex is assembled. Addition of ATP to the reaction enables the DnaK and DnaJ heat shock proteins to mediate a partial disassembly of the fourth-stage complex. These protein disassembly reactions activate the intrinsic helicase activity of DnaB and result in localized unwinding of the ori lambda template. The protein disassembly reactions are described in the accompanying articles.
Civil Rights for Whom?: Gay Rights versus Religious Freedom

Disapproval of homosexuality is widespread, deep-rooted and of long standing. Often this disapproval is tied to religion including, for nearly 3,000 years, the religions of "the Book" - Judaism, Christianity and Islam. In the last forty years a movement to change the treatment of homosexuality has emerged in the West. This movement first sought only tolerance. Now it demands acceptance of homosexuality as legally and socially equal to heterosexuality. The demand for approval has brought the gay movement into conflicts with "traditional" religion that flare throughout our culture. This war is not amenable to compromise. The goals of the gay movement are not primarily economic; most gays already have above-average incomes. Because of the pervasive influence of religion in America, equal acceptance of homosexuality cannot be achieved unless religious groups either surrender and affirm this equality or, at least, those that do not are reduced to a despised minority forced to keep its views to itself. Since the gay movement's goals are not primarily economic, it cares about the law not so much for its financial impact as for its symbolic or expressive significance. Since the prize is a symbol, compromise is unacceptable except, perhaps, as a temporary tactic: anything less than full equality is inferior, second-class status, intolerable. Full legal and social equality of homosexuality, however, cannot be squared with respect for the traditional religions that disapprove of it. If government treats homosexuality as equal to heterosexuality and by nondiscrimination laws compels citizens to do likewise, then disparagement of homosexuality must be condemned and suppressed just as racial discrimination now is. In effect, government must declare traditional religion to be false and evil. The legal war between religion and the gay movement will not culminate in an Armageddon, a final showdown. Neither side is poised to obtain a national law providing that its claims always trump the claims of the other side. Accordingly, the war between religion and the gay movement seems fated to drag on indefinitely in innumerable battles large and small. Part I of this Article discusses general federal and state constitutions and statutes that set some boundaries for specific disputes. Part II discusses government action supporting homosexuality, including antidiscrimination laws and religious exemptions therefrom. Part III discusses actions by private institutions against employees, students, or others who manifest traditional views about homosexuality. Part IV discusses general principles in the conflict between the gay movement and religious freedom and suggests some resolutions.
Reduced Risk of Colon Cancer with High Intake of Vitamin E: The Iowa Women's Health Study

Antioxidant micronutrients, including vitamin E, vitamin C, the carotenoids, and selenium, defend the body against free radicals and reactive oxygen molecules, suggesting a potential for these dietary components in cancer prevention. To investigate whether high intakes of antioxidant micronutrients protect against colon cancer in humans, we analyzed data from a prospective cohort study of 35,215 Iowa women aged 55-69 years and without a history of cancer who completed a dietary questionnaire in 1986. Through 1990, 212 incident cases of colon cancer were documented. Adjusted for age, total vitamin E intake was inversely associated with the risk of colon cancer (P for trend < 0.0001); the relative risk for the highest compared to the lowest quintile was 0.32 [95% confidence interval (95% CI) 0.19, 0.54]. Further adjustment for total energy intake and other risk factors in proportional hazards regression had little effect on these estimates. The association was not uniform across age groups: the multivariate relative risk of colon cancer for the highest compared to the lowest quintile of total vitamin E intake was 0.16 (95% CI 0.04, 0.70) for those 55-59 years old, 0.37 (95% CI 0.12, 1.16) for those 60-64 years old, and 0.93 (95% CI 0.27, 3.25) for those 65-69 years old. Multivariate-adjusted relative risks among women with higher total intakes of vitamins A and C and beta-carotene, and among users of selenium supplements, were not significantly different from 1.0. These prospective data provide evidence that a high intake of vitamin E may decrease the risk of colon cancer, especially in persons under 65 years of age.
The first Rh-isoimmunized pregnancy

Abstract There is adequate information in the literature from which to conclude that the greatest opportunity for fetal salvage is the first Rh-sensitized pregnancy. Too many interpret this to mean that the first affected baby will be minimally or mildy involved. This report of 109 first affected pregnancies indicates that 20 per cent of the Rh-positive fetuses are severely involved, that as many as 10 per cent may require intrauterine transfusion, and that the perinatal mortality rate is 10 per cent. These data are presented to emphasize the necessity of careful antepartum assessment of the fetus during the first isoimmunized pregnancy.
Device performance characterization and modeling of recombination current in CdTe/CdS pn junction diodes

A comprehensive model of pn junction diode behaviour based on Shockley-Read-Hall (SRH) recombination theory is presented and been successfully applied to a large number CdTe photovoltaic cells in the 10%-15% efficiency range. The model accounts for the range of measured values of diode quality factor and reverse saturation current found in our devices as well as an observed relationship between these parameters.
Biological and photochemical transformations of amino acids and lignin phenols in riverine dissolved organic matter

The photo- and bio-degradation of dissolved organic matter (DOM) in water from the Broad River were investigated in laboratory experiments using a solar simulator to control the intensity and exposure of samples to irradiation. The water samples included a natural assemblage of microorganisms, and the daily exposure of samples to irradiation was varied to distinguish the relative contributions of photochemical and biological degradation. Concentrations of dissolved organic carbon (DOC) and specific components of DOM, including chromophoric DOM (CDOM), lignin phenols and amino acids, were monitored to investigate the reactivity and predominant pathway of degradation of these DOM components. Biodegradation was primarily responsible for the overall remineralization of DOC and losses of the amino acid component of DOM, whereas photodegradation was primarily responsible for losses of the chromophoric and lignin phenol components of DOM. The rates of photodegradation of lignin phenols were strongly influenced by the presence of methoxy groups on the aryl ring. Syringyl (S) phenols have two methoxy substitutions, vanillyl (V) phenols have one methoxy substitution, and p-hydroxy (P) phenols are not substituted with methoxy groups. Photochemical decay constants were highest for S phenols, lowest for P phenols and followed a consistent pattern (S > V > P) in the experiments. The carbon-normalized yields of amino acids and lignin phenols were found to be useful molecular indicators of the highly reactive (i.e. labile) components of biodegradable and photodegradable DOM, respectively.
To evaluate the safety and efficiency of low level laser therapy (LLLT) in treating decubitus ulcers: a review

Introduction: Pressure sores (decubitus ulcer) are a serious problem in health care management, especially for middleaged to older people who are bed-ridden. Although preventative measures are used, the condition remains common and development of novel, improved treatment methods are desirable. This article reviews the application of laser-based methods, previously shown to be effective in accelerating wound-healing in animal models and in the treatment of decubitus ulcers in humans. Methods: About 23 scientific articles on the effect of low level laser therapy (LLLT) on wound healing in animals and humans from 2000-2014 were reviewed. Additionally, results of several randomized controlled trials (RCTs) were reviewed, and compared with other treatment methods available. Results: Whilst carefully controlled, laboratory-based animal studies indicated that LLLT can reduce healing time for several types of injuries, however similar studies in humans failed to demonstrate consistent beneficial effects in the clinical setting. An acceleration of decubitus ulcer healing has been occasionally found, although limited to certain wavelengths and sometimes only in combination with other types of therapies. Indeed, some of the clinical articles indicated that certain laser wavelengths can have detrimental effects on time of healing. Conclusions: To date, there remains no convincing evidence that LLLT has consistent medical benefit in treating decubitus ulcers. Caution should be applied when considering LLLT since only certain wavelengths utilized have shown beneficial effects. It is concluded that, more RCTs are needed since, there is no clinical justification for LLLT, alone or in combination with other methods, in treating decubitus ulcers.
A Pseudo-Rigid-Body Model of the Human Spine to Predict Implant-Induced Changes on Motion

Injury, instrumentation, or surgery may change the functional biomechanics of the spine. Adverse changes at one level may affect the adjacent levels. Modeling these changes can increase the understanding of adjacent-level effects and may help in the creation of devices that minimize adverse outcomes. The current modeling techniques (e.g., animal models, in vitro testing, and finite element analysis) used to analyze these effects are costly and are not readily accessible to the clinician. It is proposed that the pseudo-rigid-body model(PRBM) may be used to accurately predict adjacent level effects in a quick and cost effective manner that may lend itself to a clinically relevant tool for identifying the adjacent-level effects of various treatment options for patients with complex surgical indications. A PRBM of the lumbar spine (lower back) was developed using a compliant mechanism analysis approach. The global moment-rotation response, relative motion, and local moment-rotation response of a cadaveric specimen were determined through experimental testing under three conditions: intact, fused, and implanted with a prototype total disc replacement. The spine was modeled using the PRBM and compared with the values obtained through in-vitro testing for the three cases. The PRBM accurately predicted the moment-rotation response of the entire specimen. Additionally, the PRBM predicted changes in relative motion patterns of the specimen. The resulting models show particular promise in evaluating various procedures and implants in a clinical setting and in the early stage design process.
Tolerance to the locomotor-activating effects of 3,4-methylenedioxymethamphetamine (MDMA) predicts escalation of MDMA self-administration and cue-induced reinstatement of MDMA seeking in rats

Pre-clinical studies of individual differences in addiction vulnerability have been increasing over recent years, but the amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) has received relatively little attention in this regard. Previously, we reported large individual differences both in rats' initial behavioral response to experimenter-administered MDMA and their degree of behavioral sensitization to repeated administration. To determine whether these differences could predict subsequent patterns of MDMA-taking or -seeking behaviors we used the self-administration-extinction-reinstatement model to examine addiction-like behavior (i.e., escalation of MDMA self-administration and cue-induced reinstatement of MDMA seeking) in rats a priori characterized for either locomotor sensitization or tolerance to MDMA. Rats that developed tolerance to the locomotor-activating effects of MDMA had a significantly larger locomotor response to the first MDMA injection relative to rats that developed sensitization. Importantly, rats that developed tolerance subsequently displayed an escalation of MDMA self-administration over days, as well as clear cue-induced reinstatement of MDMA seeking following extinction. Conversely, rats that developed locomotor sensitization to MDMA subsequently maintained relatively stable levels of MDMA self-administration over days and showed no cue-induced reinstatement of MDMA seeking. These results show that differences in the level of psychomotor activation following acute and repeated MDMA administration can reliably predict two important addiction-like behaviors in rats, which may have implications in the prediction of compulsive MDMA use in humans.
Pragmatic motivations for the development of evidential and modal meaning in the construction “be supposed to X”

The English construction “be supposed to X” is used in a variety of functions in Present-day English, including evidential, epistemic, and deontic functions. This research offers description and explanations for the development of the evidential, epistemic, and deontic functions from an earlier passive construction, through distinct processes of reanalysis (Hopper and Traugott 1993). I argue that the motivations for these semantic and syntactic shifts are motivated by pragmatic inferences based on: discourse function, discourse expectations about human subjects, frequency effects related to semantic properties of the construction in discourse, and reader-writer expectations about genre type. The results indicate that the evidential function is not part of the general category of epistemicity for this construction, following de Haan (1999, 2001b); that this construction does not exhibit the predicted pathway of semantic development from deontic to epistemic functions (Traugott 1989) due to constraints imposed by the source construction; and that genre plays an important role not only in the relative frequency of the construction (Biber et al. 1999), but also in the emergence of the deontic function diachronically. Finally, I situate the construction in relation to cross-linguistic patterns (Bybee et al. 1994), noting how it parallels broader patterns in the development of the deontic function.
Role of Circulating Osteogenic Progenitor Cells in Calcific Aortic Stenosis

Objectives The purpose of this study was to determine the role of circulating endothelial progenitor cells with osteoblastic phenotype (EPC-OCN) in human aortic valve calcification (AVC). Background Recent evidence suggests that rather than passive mineralization, AVC is an active atherosclerotic process with an osteoblastic component resembling coronary calcification. We have recently identified circulating EPCs with osteogenic properties carrying both endothelial progenitor (CD34, KDR) and osteoblastic (osteocalcin [OCN]) cell surface markers. Methods Blood samples from controls (n = 22) and patients with mild to moderate calcific aortic stenosis (mi-moAS, n = 17), severe calcific AS (sAS, n = 26), and both sAS and severe coronary artery disease (sCAD) (n = 33) were collected during diagnostic coronary angiography. By using flow cytometry, peripheral blood mononuclear cells were analyzed for CD34, KDR, and OCN. Resected normal and calcified aortic valves were analyzed histologically. Results Patients with mi-moAS and patients with sAS/sCAD had significantly less EPCs (CD34+/KDR+/OCN−) than controls. Patients with sAS showed significantly higher numbers of EPC-OCN (CD34+/KDR+/OCN+) than controls. In addition, the percentage of EPC costaining for OCN was higher in all disease groups compared with controls. A subgroup analysis of younger patients with bicuspid sAS showed a similar pattern of significantly lower EPCs but a high percentage of coexpression of OCN. Immunofluorescence showed colocalization of nuclear factor kappa-B and OCN in diseased and normal valves. CD34+/OCN+ cells were abundant in the endothelial and deeper cell layers of calcific aortic valve tissue but not in normal aortic valve tissue. Conclusions Circulating EPC-OCN may play a significant role in the pathogenesis and as markers of prognostication of calcific AS.
Quantitation of agmatine by liquid chromatography with laser-induced fluorescence detection

Abstract A high performance liquid chromatography (HPLC) method is described for the determination of agmatine, an endogenous neuromodulator. The method involves pre-column derivatization of the sample with a fluorescent tagging reagent, 7-fluoro-4-nitrobenzoxadiazole (NBD-F). The resulting agmatine derivative is stable and can be readily extracted into ethyl acetate at pH 8.5. The extraction enhances the quantification of low level agmatine because it eliminates chromatographic peaks caused by endogenous amino acids. The HPLC separation is carried out on a C8 reversed phase column and completed in less than 10 min. With laser-induced fluorescence (LIF) detection, the detection limit is 5×10−9 M agmatine. Method precision (coefficient of variation) is 5% for agmatine in human plasma at the sub-μM level. This method has been validated by determination of agmatine in biological samples including human plasma and rat brain and stomach tissues.
Afferent contributions to intermediate area of the cat ventral medullary surface during mild hypoxia

The intermediate area of the cat ventral medullary surface activates to mild hypoxia. Carotid body and vagal afferent contributions to this response were examined by recording activity levels, measured as changes in scattered 660 nm light, from the medullary surface in 7 anesthetized, spontaneously breathing cats following 12% O2 in N2 ventilatory challenge. A miniaturized video camera collected images synchronous with the peak of cardiac R wave at 1/s, from a 3.2 mm diameter area, before, and following bilateral carotid sinus denervation (CSD) and vagotomy. In intact animals, hypoxia increased activity; however, greater increases in activity levels followed CSD, while vagotomy elicited a marked reduction of the response. Thus, carotid body afferents exert inhibitory or disfacilitatory influences on intermediate area neurons, while the vagus appears to play an excitatory role.
Neutron charge radius and the neutron electric form factor

For nearly forty years, the Galster parametrization has been employed to fit existing data for the neutron electric form factor, G{sub E}{sup n}, vs the square of the four-momentum transfer, Q{sup 2}. Typically this parametrization is constrained to be consistent with experimental data for the neutron charge radius. However, we find that the Galster form does not have sufficient freedom to accommodate reasonable values of the radius without constraining or compromising the fit. In addition, the G{sub E}{sup n} data are now at sufficient precision to motivate a two-parameter fit (or three parameters if we include thermal neutron data). Here we present a modified form of a two-dipole parametrization that allows this freedom and fits both G{sub E}{sup n} (including recent data at both low and high four-momentum transfer) and the charge radius well with simple, well-defined parameters. Analysis reveals that the Galster form is essentially a two-parameter approximation to the two-dipole form but becomes degenerate if we try to extend it naturally to three parameters.
History and the Public Purpose.

The recent survey by the Journal of American History clearly shows that historians approach their subject with a goal of improving the present and that they endeavor to engage the public in their efforts. Just as clearly, however, the survey also shows that while they value the utility of history for today, the connection between the past and the present is often indirect and may be evident only ultimately. Similarly, while historians value communicating with the public, their view of the public is dominated by traditional college classroom demographics. The public purpose is larger in our values and commitments than it is in our practice. It need not be so. Responses to the question "In addition to personal fulfillment, what value or worth do you experience in doing history?" indicated a strong desire to communicate with the public. Some responses in the sample that I reviewed were explicit, offering such answers as "helping nonacademics think differently about the world," or "teaching broadly defined to a variety of different publics," receiving "feedback from members of the public," "public discussion of diverse cultural experiences across time and place," and "communicating to a large audience." Most respondents, though, seemed to define the public served as "students and readers," and most historians could probably repeat the words of the respondent who said, "Aside from my own scholarship, my experience in 'doing history' has been largely limited to the teaching of undergraduate college students." Again, the commitment appears to be there, but the conception of the public is narrower or more remote than 'public" usually suggests. Likewise it comes as no surprise that historians place a premium on the value of history to us today. The decision to pursue the serious study of history often originates in an assumed and valued connection between the past and the present. In the survey responses to the same question about satisfaction "in doing history," some used history to make a direct and immediate contribution, as one person expressed it, to "the good of the commonweal." Some observed that history reveals "keys in
The UNESCO book production statistics

UNESCO’SStatistical Yearbook annually provides figures for the production of books in English, French, German, Spanish, and Russian. A detailed analysis of these data show that the lack of responses to questionnaires is the primary contributor to gaps in the statistics. If nonresponding countries had provided the requested information, the statistics would have shown increasing production of books in these languages. The 1987 questionnaire is reproduced in the Appendix.
LEARNING TO SOLVE PROBLEMS FROM EXERCISES

It is a common observation that learning easier skills makes it possible to learn the more difficult skills. This fact is routinely exploited by parents, teachers, textbook writers, and coaches. From driving, to music, to science, there hardly exists a complex skill that is not learned by gradations. Natarajan's model of “learning from exercises” captures this kind of learning of efficient problem solving skills using practice problems or exercises (Natarajan 1989). The exercises are intermediate subproblems that occur in solving the main problems and span all levels of difficulty. The learner iteratively bootstraps what is learned from simpler exercises to generalize techniques for solving more complex exercises. In this paper, we extend Natarajan's framework to the problem reduction setting where problems are solved by reducing them to simpler problems. We theoretically characterize the conditions under which efficient learning from exercises is possible. We demonstrate the generality of our framework with successful implementations in the Eight Puzzle, symbolic integration, and simulated robot planning domains illustrating three different representations of control knowledge, namely, macro-operators, control rules, and decision lists. The results show that the learning rates for the exercises framework are competitive with those for learning from problems solved by the teacher.
Thyroid peroxidase autoantibody fingerprints in hypothyroid and euthyroid individuals. I. Cross-sectional study in elderly women.

Human monoclonal immunoglobulin G-class autoantibodies to thyroid peroxidase (TPO), expressed as recombinant F(ab), are powerful tools for analyzing the individual components of polyclonal serum TPO autoantibodies. Four TPO-specific F(ab) interact with epitopes in two closely related domains (A and B) in the immunodominant region on TPO. In the present study, these TPO F(ab) were used to compete for serum autoantibody binding to [125I]TPO to determine the "epitopic fingerprints" in two groups of carefully controlled individuals. All individuals (14 hypothyroid and 32 euthyroid) were elderly women (60-71 yr old) with similar genetic and environmental backgrounds as well as comparable levels of serum TPO autoantibodies. Using the pool of four F(ab), serum TPO autoantibody binding was inhibited to the same extent (approximately 90%) in hypothyroid and euthyroid individuals, demonstrating that the majority of TPO autoantibodies in both groups recognize the TPO immunodominant domain. When tested individually, ...
Relationships among structural parameters of virions of helical symmetry.

Abstract Elongated helical plant viruses fall into four distinct groups; virions in each group contain the same amount of nucleic acid per unit length and have a characteristic radial location of the nucleic acid from the particle core. Each coat protein subunit associates with an integral number of nucleotide residues. The increase in the molecular weight of the protein subunits of helical viruses is accompanied by a corresponding increase in the number of nucleotide residues associated with each subunit and the increased subunit mass results in increased subunit dimension parallel to the local RNA.
Partial purification and characterization of an alkaline proteinase from the rabbit testis

A proteolytic enzyme capable of cleaving intact proteins and synthetic substrates α−N−benzoyl−DL−arginine β−naphthylamide (Bz-Arg-NNap), α-N-benzoyl-L-arginine p-nitroanilde (Bz-Arg-NPhNO2), and α-N-benzoyl-L-arginine ethyl ester (Bz-Arg-OEt) was purified 92– fold from the rabbit testes. The enzyme exhibited optimal activity at pH 9.0 and 50°C. The polyacrylamide gel electrophoresis and sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis of the purified enzyme demonstrated multiple forms; the major band in the SDS-polyacrylamide gel electrophoresis corresponded to a Mt 48,000. The same value was established by the gel filtration over Sephadex G-75. The rabbit testicular alkaline proteinase (TAP) resembled acrosin in the hydrolysis of Bz-Arg-OEt. However, CaCl2, a potential stimulator of acrosin activity, inhibited the alkaline proteinase. The strong inhibitors of acrosin, eg pheny methyl sulphonyl fluoride (PMSF), tosyl lysine chloromethyl ketone (TLCK), and benzamidine did not inhibit the alkaline proteinase. TAP was activated by an acrosin inhibitor isolated from the rabbit testes. Since 0.5 M KCl was necessary for complete extraction of the enzyme and the bulk of the activity was present in 9,000g pellet of the testicular homogenate. The alkaline proteinase appeared to be associated with the membranous structures.
Energy efficiency of distributed cooperative relaying

Distributed cooperative relaying is an attractive method to combat fading in wireless communications because of its performance advantages, simplicity, scalability, and low overhead. In [1], the spectral efficiency of two previously proposed distributed relaying strategies is investigated: Timer-based Best-Select relaying and M-group Dis-STBC All-Select relaying. From the perspective of spectral efficiency, M-group Dis-STBC All-Select relaying outperforms Best-Select relaying; however, when every node in the decoded set retransmits the source message, much more power will be consumed. In this paper, the energy efficiency of these two relaying strategies is studied to provide a more comprehensive guide for system designers to determine which strategy fits a specific application. Numerical results indicate that, although Best-Select relaying conserves transmit power, in some cases, it is also less energy efficient than M-group Dis-STBC All-Select relaying.
HIRIS - The High Resolution Imaging Spectrometer

The High-Resolution Imaging Spectrometer (HIRIS) is a JPL facility instrument designed for NASA's Earth Observing System (Eos).It will have 10-nm wide spectral bands from 0.4-2.5 microns at 30 m spatial resolution over a 30 km swath. The spectral resolution allows identification of many minerals in rocks and soils, important algal pigments in oceans and inland waters, spectral changes associated with plant canopy biochemistry, composition of atmospheric aerosols, and grain size of snow and its contamination by absorbing impurities. The bands wil have 12-bit quantization over a dynamic range suitable for bright targets, such as snow. For targets of low brightness, such as water bodies, image-motion compensation will allow gains up to a factor of eight to increase signal-to-noise ratios. In the 824-km orbit altitude proposed for Eos, the crosstrack pointing capability will allow 4-5 views during a 16-day revisit cycle.
Homonym understanding and conservation

Abstract It is proposed that a common cognitive capacity underlies both homonym understanding and conservation ability—namely, the capacity to shift attention from one dimension (domain) to another. This hypothesis is tested in a longitudinal study of kindergarten (mean age 6-0) and first-grade (mean age 6-6) children. The results indicate that conservation status is significantly related to homonym understanding, over and above the age or general vocabulary level of the child.
Mitochondrial cytochrome deficiency presenting as a myopathy with hypotonia, external ophthalmoplegia, and lactic acidosis in an infant and as fatal hepatopathy in a second cousin

Fatal infantile mitochondrial myopathy with lactic acidosis, morphologically abnormal mitochondria, deficient cytochromes aa3 and b, and a Fanconi-like aminoaciduria has been described. We report two infants, second cousins, with a similar fatal mitochondrial disorder, the cytochrome deficiency limited to skeletal muscle in one child and to liver in the other. The first child at 3 months of age had weight loss, hypotonia, external ophthalmoplegia, and a severe lactic acidosis with a high lactate/pyruvate ratio. Electron microscopy of muscle showed marked proliferation of enlarged mitochondria, many containing concentric rings of cristae. In skeletal muscle mitochondria, cytochromes aa3 and b were not detectable but cytochrome cc was found to be normal by spectroscopy. Cytochrome c oxidase activity was less than 1% of normal. Mitochondria from kidney, liver, heart, lung, and brain examined postmortem had normal cytochromes and preserved cytochrome c oxidase activity. The second cousin at 5 months of age had weight loss and hepatomegaly but no systemic lactic acidosis. Liver biopsy showed hepatocytes packed with enlarged mitochondria. The liver mitochondria showed deficient cytochromes aa3 and b postmortem, and cytochrome c oxidase activity was less than 10% of normal. Kidney mitochondria had normal cytochromes. Muscles was not studied. The mitochondrial abnormality in the two cousins presumably is related. Unexplained are the mode of genetic transmission or environmental exposure and the apparent involvement of a single different organ in each child.
Topics in Strong Langmuir Turbulence

Progress in two approaches to the study of strong Langmuir turbulence is reported. In two spatial dimensions, numerical solution of the Zakharov equations yields a steady state involving linear growth, linear damping, and a collection of coherent, long-lived entities which might loosely be called solitons. In one spatial dimension, a statistical theory is applied to the cubically nonlinear Schroedinger equation and is solved analytically in a special case.
Diagnostic Localization of Pheochromocytoma

Pheochromocytoma is a rare but clinically important tumor of catecholamine-secreting chromaffin cells. This tumor constitutes a surgically curable cause of hypertension. Therefore, correct localization of pheochromocytoma is essential for effective management of this tumor. Several conventional and nuclear imaging modalities are currently available to localize pheochromocytoma. Computed tomography (CT) and magnetic resonance imaging (MRI) have good sensitivity but poor specificity for detecting pheochromocytoma, and nuclear imaging approaches such as (131)I-metaiodobenzylguanidine scintigraphy or [(111)In]-DTPA-D-Phe-pentetreotide (Octreoscan) have limited sensitivity. However, specificity of (131)I-metaiodobenzylguanidine scintigraphy is very good and this means of imaging provides a method for confirming that a tumor is a pheochromocytoma and rules out metastatic disease. Recently, we introduced a new imaging method, 6-[(18)F]fluorodopamine positron emission tomography, that can be used successfully for the detection of solitary and metastatic pheochromocytomas. Our preliminary data suggest that this method is superior to other nuclear imaging methods including metaiodobenzylguanidine and octreotide scintigraphy. In this report we provide an update regarding nuclear imaging of primary and metastatic pheochromocytoma, particularly using 6-[(18)F]fluorodopamine positron emission tomographic scanning.