cssi/SciSciGPT-SciSciNet huggingface dataset:
Probing the consequences of antenna modification in cyanobacteria

Photosynthetic organisms rely on antenna systems to harvest and deliver energy from light to reaction centers. In fluctuating photic environments, regulation of light harvesting is critical for a photosynthetic organism’s survival. Here, we describe the use of a suite of phycobilisome mutants to probe the consequences of antenna truncation in the cyanobacterium Synechocystis sp. PCC 6803. Studies using transmission electron microscopy (TEM), hyperspectral confocal fluorescence microscopy (HCFM), small-angle neutron scattering (SANS), and an optimized photobioreactor system have unraveled the adaptive strategies that cells employ to compensate for antenna reduction. As the phycobilisome antenna size decreased, changes in thylakoid morphology were more severe and physical segregation of the two photosystems increased. Repeating distances between thylakoid membranes measured by SANS were correlated with TEM data, and corresponded to the degree of phycobilisome truncation. Thylakoid membranes were found to have a high degree of structural flexibility, and changes in the membrane system upon illumination were rapid and reversible. Phycobilisome truncation in Synechocystis 6803 reduced the growth rate and lowered biomass accumulation. Together, these results lend a dynamic perspective to the intracellular membrane organization in cyanobacteria cells and suggest an adaptive mechanism that allows cells to adjust to altered light absorption capabilities, while highlighting the cell-wide implications of antenna truncation.
Attention can either increase or decrease spike count correlations in visual cortex

Visual attention enhances the responses of visual neurons that encode the attended location. Several recent studies have shown that attention also decreases correlations between fluctuations in the responses of pairs of neurons (termed spike count correlation or r(SC)). These results are consistent with two hypotheses. First, attention-related changes in rate and r(SC) might be linked (perhaps through a common mechanism), with attention always decreasing r(SC). Second, attention might either increase or decrease r(SC), possibly depending on the role of the neurons in the behavioral task. We recorded simultaneously from dozens of neurons in area V4 while monkeys performed a discrimination task. We found strong evidence in favor of the second hypothesis, showing that attention can flexibly increase or decrease correlations depending on whether the neurons provide evidence for the same or opposite choices. These results place important constraints on models of the neuronal mechanisms underlying cognitive factors.
The Effect of a Child Pedestrian Safety Street Program on Improving Knowledge

Children between the ages of 5 to 8 years are at risk for pedestrian, motor vehicle, bicycle, stranger, and animal bite injuries. This article discusses the use of Safety Street, a program developed to educate children in this age group about safe behaviors using didactic teaching and practical training in a mobile three-dimensional Safety Street. The study's goal was to demonstrate the effectiveness of this method on improving knowledge in these safety areas. Intervention school children were tested 1 week prior to the Safety Street program arrival, one month later, and 4-6 months later. Control school children were tested 4-6 months prior to Safety Streets arrival, one-month later, and right before Safety Street's arrival. There were 371 control subjects and 369 intervention subjects who took test 1 and test 2, with a mean age of 6.4 and 6.8 years respectively. The control school subjects were 47% male and the intervention school subjects were 53% male. Overall, intervention subjects increased 12% on test scores compared to an increase of 5% in the control subjects. This difference was also observed when stratified by grade. For those students who took test 3 (96 intervention group and 342 control group students). The greatest improvement was shown in kindergarten children and mean scores increased with age. The authors conclude that the Safety Street program is an effective means of transmitting knowledge about pedestrian, bicycle, animal, and passenger safety to children between the ages of 5 to 8 years. The increase in knowledge is retained after 4 to 6 months.
Preparation of metallo-dielectric metamaterials by multi-photon direct laser writing

Three-dimensional metallo-dielectric photonic crystals were created by preparing a polymeric micro-scaffold using multi-photon direct laser writing and conformally metallizing the structures by electroless deposition. The resulting metamaterials behave at infrared wavelengths like metal photonic crystals.
The Collapse of the Middle Way: Senate Republicans and the Bipartisan Foreign Policy, 1948-1952

Preface Introduction The Origins of Bipartisanship, 1942-1948 The North Atlantic Treaty and the Military Assistance Program, January-September 1949 The Senate and the Fall of China, 1949 The Republicans and Formosa, October 1949-January 1950 McCarthyism and Bipartisanship, January-June 1950 Bipartisanship and the Korean War, June-November 1950 The Great Debate of 1951 MacArthur and the Demise of the Old Bipartisanship Dulles, Eisenhower, and the New Bipartisanship Conclusions Abbreviations in Notes Notes to Chapters Note on Sources Index
Mini-exon gene repeats of Trypanosoma (Nannomonas) congolense have internal repeats of 190 base pairs

Genomic DNA hybridizations reveal that the mini-exon gene repeats of Trypanosoma (Nannomonas) congolense contain from one to greater than 20 internal tandem repeats of 190 base pairs (bp). The sequences of two mini-exon gene repeats were determined, one with three internal 190 bp repeats and one with a single 190 bp sequence. These internal repeats appear just after a very dC/dT-rich region, in the non-transcribed spacer regions between adjacent mini-exon transcription units. They do not occur in the genomes of the three other Trypanosoma species nor in the mini-exon gene repeats of four other kinetoplastids previously investigated. The mini-exon coding region of T. congolense differs in four positions from the T. brucei mini-exon sequence and in one position from a consensus sequence of the mini-exons found in other trypanosomatids. Pulse field gradient gels show that the mini-exon gene repeats of T. congolense are on large, greater than 2 megabase pair, chromosome(s).
Alteration of serum enzymes in clinical myocardial infarction

Abstract Forty-two patients with myocardial infarction were studied, and the results of alteration in the activities of SGO-T, LD, and MD are reported. Whereas the enzyme activities of all three enzymes, SGO-T, LD, and MD, are usually elevated in infectious hepatitis, metastatic liver disease, and sickle cell anemia during crisis, they may also be elevated in cirrhosis of the liver and a variety of noncardiac conditions. However, the serially determined enzyme activities of all three enzymes in the above-named conditions are not in keeping with the pattern seen in myocardial infarction. Angina is not usually associated with an elevated enzyme activity.
Spatially Dissecting the Viscoelastic Recoil and Cell Shape Contributions of Actomyosin Stress Fiber Bundles

The ability of a living cell to distribute contractile stresses against the extracellular matrix (ECM) in a spatially heterogeneous fashion underlies many fundamental behaviors, including motility, polarity, and assembly into multicellular tissues. Here we investigate the biophysical basis of this phenomenon at unprecedented spatial and mechanical resolution by using femtosecond laser ablation to sever contractile stress fibers located in specific cellular compartments and measure regional variations in fiber viscoelastic retraction and contribution to cell shape stability. Upon photodisruption, myosin light chain kinase-dependent stress fibers located along the cell periphery recoil much more slowly than rho-associated kinase-dependent stress fibers located in the cell center, with severing of peripheral fibers uniquely triggering a dramatic contraction of the entire cell. Remarkably, selective pharmacological dissipation of peripheral fibers significantly accelerates the retraction of central fibers, suggesting transference of tensile loads from one population of stress fibers to another in order to stabilize cell shape. These results suggest that stress fibers regulated by different myosin activators exhibit different mechanical properties and cell shape contributions. These data also illustrate the potential of femtosecond laser ablation to spatially map the microscale contractile mechanics of living cells.
The Detection of Fake Good and Fake Bad on the MMPI-2.

The efficacy of the F, K, L, F-K, and O-S scales of the MMPI-2 in detecting fake good, fake bad, and honest profiles was investigated. A total of 110 undergraduate educational psychology students were administered the MMPI-2 under instructions to fake good, fake bad, or respond honestly. Multiple analysis of variance resulted in a significant (p < .001) difference on all validity scale scores of the three groups of respondents.
Lord Acton's Irish elections

From the age of twenty-three until his death at the age of sixty-eight, Lord Acton was or sought to be a member of the United Kingdom parliament. Although Acton remains a subject of scholarly interest, his political career has received relatively little attention. This article examines Acton's search for an Irish parliamentary seat, a search which was twice unsuccessful in 1857, but which resulted in May 1859 in Acton's return as the member for Carlow borough. Although Acton was pushed towards parliament by his family – and particularly his stepfather, Lord Granville – a close examination of Acton's campaigns reveals more dedication to a political career than has previously been accepted.
Increased inositol 1,4,5-trisphosphate accumulation correlates with an up-regulation of bradykinin receptors in Alzheimer's disease.

An alteration in signal transduction systems in Alzheimer's disease (AD) would likely be of pathophysiological significance, because these processes control normal brain functions. Previously, a diminished β-adrenergic-mediated cyclic AMP response was found in cultured fibroblasts from AD patients. Because cross-talk between the phosphoinositide and cyclic AMP pathways exists, the phosphoinositide cascade was studied under conditions that were similar to those for studying the cyclic AMP response. Cells from AD patients and agematched controls responded to bradykinin (BK) and released inositol 1,4,5-trisphosphate [Ins (1,4,5) P 3 ] in a time- and dose-dependent manner. The level of Ins(1,4,5)P 3 increased rapidly and transiently in response to BK, peaked at 5 s, but still remained 116-132% above the basal level by 30 s. Although the temporal patterns were similar in both groups, the Ins(1,4,5)P 3 concentrations in AD fibroblasts were 73 and 89% above levels in the age-matched controls at 5 and 10 s, respectively. Prostaglandin E 1 also increased Ins(1,4,5) P 3 formation, but this response was not different between the two groups. Although K D (affinity) values for the BK receptor were similar in both control and AD cells, the number of BK receptors (B max ) was significantly elevated in AD fibroblasts (186.8±0.8 fmol/mg of protein) as compared with control fibroblasts (57.2±15.3 fmol/mg of protein). These results indicate that the elevated Ins(1,4,5)P 3 production in response to BK in AD fibroblasts is positively correlated with an increase in the receptor numbers
Socialization to the chronic sick role in later life. An interactionist view.

This study examines sick role identification and sick role retention as interrelated aspects of socialization to a chronic sick role. Focusing on physically impaired older people (55-85) and adopting an interactionist view, sick role socialization is seen in terms of both conformity (mirroring the role casting of others) and improvisation (portraying sickness in pursuit of social support, legitimated dependency, and relief from social strain). Both models are generally supported by the data.
Protein-Protein Interaction Domains and the Heterodimerization of Thyroid Hormone Receptor Variant α2 with Retinoid X Receptors

Heterodimerization between thyroid hormone receptors (TRs) and retinoid X receptors (RXRs) is mediated by a weak dimerization interface within the DNA- binding domains (DBDs) and a strong interface within the C-terminal ligand- binding domains of the receptors. Previous studies have shown that the conserved ninth heptad in the TR ligand-binding domain appears to play a critical role in heterodimerization with RXR. However, despite lacking the full ninth heptad, TR variant alpha2 (TRv alpha2) can heterodimerize with RXR on specific direct repeat response elements, but not on palindromic elements or in solution. Two possibilities may account for TRv alpha2-RXR heterodimerization on direct repeats. First, the DBD of TRv alpha2 may play a critical role in heterodimerization with RXR. Second, a specific sequence within the unique C terminus of TRv alpha2 may promote the formation of TRv alpha2-RXR heterodimers. In this study, we used receptor chimeras in which the DBD of RXR was replaced by either the TR DBD or an unrelated DBD from the metalloregulatory transcription factor AMT1 to address the role of the DBD dimerization interface in TRv alpha2-RXR heterodimerization. Gel mobility shift analyses showed that whereas TR alpha1 formed heterodimers with these chimeras, TRv alpha2 failed to do so. Deletion of the unique C terminus of TRv alpha2 had only a marginal effect on heterodimerization with RXR. Mutations within the DBD dimerization interface abolished heterodimerization of full-length TRv alpha2 with RXR but only marginally affected heterodimerization of full-length TR alpha1 with RXR. These data support the hypothesis that the TR-RXR DBD dimerization interface plays a critical role in TRv alpha2-RXR heterodimerization. Additional data show that the amino acid residues that make direct TR-RXR contacts within the DBDs also may play a role in receptor monomer binding to DNA, since mutations within these residues severely impair this interaction.
Instream flow studies in perspective

The Instream Flow Incremental Methodology (IFIM) has been subject to criticisms, including its apparent imprecision, inability to predict discharge-biomass relationships, lack of independence of hydraulic variables, and omission of predation/competition as variables in assessing the dynamics of aquatic populations and communities. This paper addresses criticisms of the methodology, stressing three themes. First, the development of IFIM to its present form is described. The goal of the method is to relate biotic values in equivalent terms to those used to estimate other beneficial uses of water. As such the engineering concepts of hydraulic simulation and suitability criteria play a strong role in the model. Previous studies suggest that IFIM appears to perform defensibly in coldwater systems but less well in more complex coolwater and warmwater systems. Second, the strengths of IFIM are considered and the type of environmental of IFIM are considered and the type of environmental problems it is suited to address are described. Research suggests that biotic responses vary dramatically as certain threshold discharges are approached and it is suggested that biomass predictions are inappropriate with current versions of IFIM. Its greatest utility is shown to be in assessing the impacts of water resources development on habitat availability for aquatic organisms. Third, the limitations of IFIM are presented; those that appear to have merit and those that arise from misapplication or misunderstanding of the methodology. We suggest that suitability criteria be developed on a site specific basis and include depth-velocity dependent functions. The added predictive power by incorporation of coefficients of biological interactions to this management model is probably not justified by the expense required to obtain the data. As a tool, IFIM maximizes generality and precision at the expense of ecological reality but this does not detract from its utility to analyse water resource issues.
Comparison of the Recovery of Mycobacterium Bovis Isolates Using the BACTEC MGIT 960 System, BACTEC 460 System, and Middlebrook 7H10 and 7H11 Solid Media

The BACTEC Microbacteria Growth Indicator Tube (MGIT) 960 system was evaluated to determine how it compares with the BACTEC 460 radiometric system and solid media for recovery of Mycobacterium bovis from tissue samples. A total of 506 bovine lymph node samples were collected from abattoirs in the United States and Mexico between November 2003 and September 2004. Processed samples were inoculated into an MGIT 960 tube, BACTEC 460 vial, and Middlebrook 7H10 and Middlebrook 7H11 solid media. Ziehl-Neelsen slides were prepared to check for contaminants and confirm the presence of acid-fast positive bacilli. Samples containing acid-fast bacilli were confirmed as members of the Mycobacterium tuberculosis complex by a nucleic acid assay. Niacin and nitrate biochemical tests were used to distinguish M. bovis from M. tuberculosis isolates. Statistical analyses were performed to compare recovery rate, mean time to detection, contamination rates, as well as pair-wise comparisons in each category. The results showed that the MGIT 960 system had a higher recovery rate of M. bovis (122/129) than did the BACTEC 460 (102/129) and solid media system (96/129). The average time to detection was 15.8 days for the MGIT 960 system, 28.2 days for the BACTEC 460 system, and 43.4 days for solid media. Contamination rates were 6.9% for the MGIT 960 system, 3.4% for the BACTEC 460 system, and 21.7% for solid media. These results indicate the MGIT 960 system can be used as an alternative to the BACTEC 460 system for recovering M. bovis from tissue samples.