cssi/SciSciGPT-SciSciNet huggingface dataset:
Theory and design of two-parallelogram filter banks

It is well known that the analysis and synthesis filters of orthonormal DFT filter banks can not have good frequency selectivity. The reason for this is that each of the analysis and synthesis filters have only one passband. Such frequency stacking (or configuration) in general does not allow alias cancellation when the individual filters have good stopband attenuation. A frequency stacking of this nature is called nonpermissible and should be avoided if good filters are desired. In a usual M-channel filter bank with real-coefficient filters, the analysis and synthesis filters have two passbands. It can be shown that the configuration is permissible in this case. Many designs proposed in the past demonstrate that filter banks with such configurations can have perfect reconstruction and be good filters at the same time. We develop the two-parallelogram filter banks, which is the class of 2-D filter banks in which the supports of the analysis and synthesis filters consist of two parallelograms. The two-parallelogram filter banks are analyzed from a pictorial viewpoint by exploiting the concept of permissibility. Based on this analysis, we construct and design a special type of two-parallelogram filter banks, namely, cosine-modulated filter banks (CMFB). In two-parallelogram CMFB, the analysis and synthesis filters are cosine-modulated versions of a prototype that has a parallelogram support. Necessary and sufficient conditions for perfect reconstruction of two-parallelogram CMFB are derived.
Constrained band selection for hyperspectral imagery

Constrained energy minimization (CEM) has shown effective in hyperspectral target detection. It linearly constrains a desired target signature while minimizing interfering effects caused by other unknown signatures. This paper explores this idea for band selection and develops a new approach to band selection, referred to as constrained band selection (CBS) for hyperspectral imagery. It interprets a band image as a desired target signature vector while considering other band images as unknown signature vectors. As a result, the proposed CBS using the concept of the CEM to linearly constrain a band image, while also minimizing band correlation or dependence provided by other band images, is referred to as CEM-CBS. Four different criteria referred to as Band Correlation Minimization (BCM), Band Correlation Constraint (BCC), Band Dependence Constraint (BDC), and Band Dependence Minimization (BDM) are derived for CEM-CBS.. Since dimensionality resulting from conversion of a band image to a vector may be huge, the CEM-CBS is further reinterpreted as linearly constrained minimum variance (LCMV)-based CBS by constraining a band image as a matrix where the same four criteria, BCM, BCC, BDC, and BDM, can be also used for LCMV-CBS. In order to determine the number of bands required to select p, a recently developed concept, called virtual dimensionality, is used to estimate the p. Once the p is determined, a set of p desired bands can be selected by the CEM/LCMV-CBS. Finally, experiments are conducted to substantiate the proposed CEM/LCMV-CBS four criteria, BCM, BCC, BDC, and BDM, in comparison with variance-based band selection, information divergence-based band selection, and uniform band selection.
Phase II trial of irinotecan in combination with amifostine in patients with advanced colorectal carcinoma

BACKGROUND Irinotecan is effective in patients with advanced colorectal carcinoma in both first-line and salvage settings but its use can be limited by serious side effects. Amifostine has been shown to reduce the incidence of cisplatin-induced cumulative renal toxicity in patients with advanced ovarian carcinoma and nonsmall cell lung carcinoma. In the current pilot Phase II trial, the authors examined the potential role of amifostine as a protective agent against irinotecan-induced diarrhea and myelosuppression and evaluated an every-2-weeks regimen as an alternative schedule for the administration of irinotecan in patients with previously treated metastatic colorectal carcinoma. METHODS All patients received amifostine, 740 mg/m2, followed by irinotecan, 250 mg/m2, every 2 weeks. A 6-week cycle of chemotherapy (every 2 weeks for 3 treatments) was chosen to assess toxicity and response. The main objective of the current study was to evaluate the impact of amifostine on gastrointestinal and hematologic toxicity. RESULTS A total of 22 patients entered the current study. Six of these 22 patients (27%) had WHO Common Toxicity Criteria Grade 3 or 4 diarrhea, including 2 patients (9%) with Grade 4 diarrhea. Eight of 22 patients (36.3%) developed Grade 3 or 4 neutropenia (Grade 4 in 4 of the 22 patients [18%]). Dose reduction was required in 25% of the treatment cycles. Five of the 22 patients (23%) withdrew from the trial due to amifostine toxicity. Of the 15 patients who were evaluable for response, 4 patients (26.6%) had achieved a partial response and 9 (60%) had stable disease as their best response. CONCLUSIONS The combination of irinotecan with amifostine in patients with previously treated metastatic colorectal carcinoma did not appear to reduce irinotecan toxicity. Amifostine did not appear to interfere with the cytotoxic effect of irinotecan. The results of the current study did demonstrate efficacy and safety of the every-2-weeks irinotecan schedule that was comparable to other established regimens and these results support its feasibility as a reasonable alternative in this disease setting. Cancer 2002;94:2174–9. © 2002 American Cancer Society. DOI 10.1002/cncr.10432
Modeling free-carrier absorption and avalanching by ultrashort laser pulses

In the past decade it was demonstrated experimentally that negatively-chirped laser pulses can lower the surface LIDT for wide band-gap materials by decreasing the number of photons required for photoionization on the leading edge of the pulse. Similarly, simulations have shown that positively-chirped pulses resulting from selffocusing and self-phase modulation in bulk dielectrics can alter the onset of laser-induced material modifications by increasing the number of photons required for photoionization on the leading edge of the pulse. However, the role of multi-chromatic effects in free-carrier absorption and avalanching has yet to be addressed. In this work a frequency-selective model of free-carrier dynamics is presented, based on a recently extended multi-rate equation for the distribution of electrons in the conduction band. In this model free-carriers gain energy from the field by single-photon absorption at the instantaneous frequency, which varies as a function of space and time. For cases of super-continuum generation it is shown that a Drude-type absorption can vary from 50% to over 200% the absorption rate as evaluated at the central pulse frequency only. Simulations applying this model to ultrafast laser-plasma interactions in fused silica explore how pulse chirps may be used as a distinguishing parameter for LID resulting from otherwise identical pulses.
Ocular Dominance, Cognitive Strategy, and Sex Differences in Spatial Ability

Ocular dominance, handedness, and cognitive strategy were assessed in relation to performance by 146 undergraduates on the Vandenberg Mental Rotation Test. Higher spatial scores were found for right-eyed subjects, right-handed subjects, and males. These higher scoring groups reported using similar cognitive strategies. The counted blocks less, used their hands less, and pictured in their minds more than the left-eyed, left-handed and female subjects. Results confirm previous findings.
The Cascading Development of Autonomy and Relatedness From Adolescence to Adulthood

A developmental cascade model of autonomy and relatedness in the progression from parent to friend to romantic relationships across ages 13, 18, and 21 was examined among 184 adolescents (53% female, 58% Caucasian, 29% African American) recruited from a public middle school in Virginia. Parental psychological control at age 13 undermined the development of autonomy and relatedness, predicting relative decreases in autonomy and relatedness with friends between ages 13 and 18 and lower levels of autonomy and relatedness with partners at age 18. These cascade effects extended into adult friendships and romantic relationships, with autonomy and relatedness with romantic partners at age 18 being a strong predictor of autonomy and relatedness with both friends and partners at age 21.
Evaluation of Radioelement Geochemistry for Detection of Petroleum Reservoirs: ABSTRACT

We tested the hypothesis that radioelements are either enriched or depleted over petroleum accumulations. Total count surveys are subject to signal variations due to changes in soil composition and to variations in soil moisture. Methods have been determined to lower the variations due to soil composition and to eliminate variations due to soil moisture. We conclude that, if hydrocarbon-related anomalies are present, they are overwhelmed by changes in soil composition. Changes in soil composition can cause: (1) a fourfold change in total count and eU, (2) a twofold change in K, and (3) a thirteenfold change in eTh. Modified eU/K, eTh/K, and eU/eTh ratios reduce the variations caused by soil composition to ±50% of normal conditions. This permits detection of anomalies as low as 1.0 ppm eU, 2.0 ppm eTh, or 0.7% K. Statistical detection limit for the surveys is ±0.24 ppm eU at 2.0 ppm eU concentration. The detected anomalies are of equal amplitude and frequency both on and off the fields. This, plus the lack of anomaly repeatability from line to line, precludes a hydrocarbon source. The majority of all anomalies are attributed to soil or lithologic sources. The others are caused by uranium mineralization. End_of_Article - Last_Page 1424------------
Continuous exposure to bright light upregulates bFGF and CNTF expression in the rat retina.

PURPOSE. To examine mRNA expression of neurotrophic factors in the retina after exposure to bright light. METHODS. Male adult Sprague-Dawley rats were exposed to light of 115–130 ft-c. Retinas were collected after 1, 2, 4 or 7 days of exposure. Northern blot analysis was performed to determine mRNA levels for the following factors and their receptors: basic fibroblast growth factor (bFGF), ciliary neurotrophic factor (CNTF), acidic fibroblast growth factor (aFGF), brain-derived neurotrophic factor (BDNF), insulin-like growth factor 1 (IGF-1) and glial fibrillary acidic protein (GFAP). Expression of bFGF, CNTF and GFAP was localized by in situ hybridization. RESULTS. Exposure to light of 115–130 ft-c resulted in a substantial increase in bFGF and CNTF expression that persisted during the entire 7-day period of exposure. The peak expression of bFGF was almost 9-fold at day 2. The increase in CNTF mRNA reached a maximum of 6-fold at day 4. A small increase (50%) in IGF-1 mRNA was also seen at day 4. Among th...
por Variable-Region Typing by DNA Probe Hybridization Is Broadly Applicable to Epidemiologic Studies of Neisseria gonorrhoeae

The porin gene (porB) of Neisseria gonorrhoeae encodes the major outer membrane protein identified as PI or Por. To examine the utility of por variable-region (VR) typing, porB from 206 isolates was characterized by using oligonucleotide probes in a checkerboard hybridization assay that identifies the sequence types of five VRs of both PIA and PIB porB alleles. The strains represented temporally and geographically distinct isolates, isolates from a large cluster, epidemiologically linked partner isolates, and a collection of strains from disseminated gonococcal infections. By using rigorous epidemiologic criteria for transmission of infection between sex partners, por VR typing was more discriminatory than serovar typing in classifying isolates from both members of 43 epidemiologically linked pairs: 39 of 43 pairs were classified as coinciding by por VR typing compared to 43 of 43 by serovar determination (P = 0.058). porB sequence data confirmed the accuracy of the por VR method. Relationships between VR type and serovar typing monoclonal antibodies were observed for all six PIB and three of six PIA antibodies. por VR typing is a molecular tool that appears to have broad applicability. This method can be adapted to a wide range of technologies from simple hybridization to microarray and may allow for typing from noncultured clinical specimens.
In vitro RNA editing-like activity in a mitochondrial extract from Leishmania tarentolae

Abstract A mitochondrial extract from Leishmania tarentolae directs the incorporation of uridylate (U) residues within the pre-edited domain of synthetic cytochrome b (CYb) and NADH dehydrogenase subunit 7 mRNA. This has several characteristics of an in vitro RNA editing activity, but no direct evidence for involvement of guide RNAs was obtained. Inhibition by micrococcal nuclease suggests a requirement for some type of endogenous RNA. The limitation of internal U-incorporation to the pre-edited region in the CYb mRNA and the inhibition by deletion or substitution of both mRNA anchor sequences for CYb gRNA-I and -II could be consistent either with a gRNA-mediated process or a secondary structure-mediated process. A low level of incorporation of [alpha-32P]CTP occurs at the same sites as UTP. Internal U-incorporation activity is selectively inhibited by heterologous RNAs, suggesting an involvement of low affinity RNA-binding proteins which can be competed by the added RNA.
Use of circular sector shaped planar circuits for multiport power divider-combiner circuits

A sector-shaped circuit configuration is proposed for designing planar power dividers/combiners that are compatible with microstrip circuits. Interesting experimental results on 2-way, 3-way, 4-way, and 5-way power divider circuits are presented. Impedance matrix expressions for annular sectors are derived and used in the two-dimensional analysis of these circuits. >
“But you said ‘four sheep’ …!”: (sign) language, ideology, and self (esteem) across generations in a Mayan family

Abstract A first generation family sign language, dubbed Z, emerging in a single extended household in an otherwise Tzotzil-speaking community of indigenous peasants in highland Chiapas, Mexico, provides an example of both rapid language creation and change and of the evolution of ideologies of appropriate language form and use in even such a minimal speech/sign community. Adding the new sign language to (the bottom end of) an existing inventory of differentially evaluated language varieties, including Tzotzil and Spanish, positions the signers with respect not only to hearing speakers, but to one another. The most striking contrast presented is between the oldest fluent signer—the first deaf person in her community—trapped by her sign language, and the youngest—her hearing son—propelled beyond it.
ALIENATION AMONG B.Ed. STUDENTS IN RELATION TO SELF-EFFICACY AND EMOTIONAL INTELLIGENCE

Present study was undertaken to investigate the significance of relationship of alienation with self-efficacy and emotional intelligence. The study was conducted on 200 B.Ed. students from Government Aided Colleges of Education for Women of Ludhiana district of Punjab, India. Alienation Scale by Ojha (2010), Self-Efficacy Scale by Mathur and Bhatnagar (2012) and Emotional Intelligence Test by Zainuddin and Ahmed (2011) were used to collect the data. The results of the study revealed significant negative relation of alienation with both self-efficacy and emotional intelligence.
The Evolutionary Ecology of Ethanol Production and Alcoholism

SYNOPSIS. Understanding the evolutionary ecology of ethanol production may yield insights into why humans are prone to excessive consumption of ethanol. In particular, Dudley (2000) suggested that human ancestors developed a genetically based attraction to ethanol because they could use its odor plume to locate fruiting trees and because of health benefits from its consumption. If so, ethanol should be common in wild fruits and frugivores should prefer fruits with higher ethanol content. A literature review reveals that ethanol is indeed common in wild fruits but that it typically occurs in very low concentrations. Furthermore, frugivores strongly prefer ripe over rotting fruits, even though the latter may contain more ethanol. (Data on ethanol content of ripe and rotting wild fruit are lacking.) These results cast doubt on Dudley’s hypothesis and raise the question of how humans became exposed to sufficiently high concentrations of ethanol to allow its excessive consumption. Because fermentation is an ancient and widespread practice, I suggest that humans ‘‘discovered’’ ethanol while using fermentation as a food preservation technique. They may have been predisposed to consume ethanol from previous and beneficial exposure to much lower doses or they may have become addicted to it at high concentrations because of fortuitous physiological responses.
Designing with HDR data: what the human development report can tell us about international users

Intercultural professional communication (IPC) requires a nuanced understanding of international users' interactions with technology and information. This requirement poses a distinct challenge to international communication and information designers who must overcome geographic, linguistic, and cultural barriers to understanding users as complex agents. The United Nations Development Program (UNDP) annually publishes a Human Development Report (HDR) that contains high-quality international statistics on the regional, national, and transnational contexts in which individuals use technology and information. Thus, the HDR can serve as a resource for communication designers working in international contexts. This article presents strategies for how communication designers might use the HDR when designing materials for users in other cultures as well as use when teaching international aspects of professional writing/communication."
Multi-scale modeling of biomaterials and tissues

Computer simulation has emerged as a powerful tool to investigate and design materials without ever making them. Predicting the properties and behavior of materials by computer simulation from the bottom-up perspective has long been a vision of computational materials scientists and, as computational power increases, modeling and simulation tools are becoming crucial to the investigation of material systems. The key to achieving this goal is using hierarchies of paradigms that seamlessly connect quantum mechanics to macroscopic systems. Particular progress has been made in relating molecular-scale chemistry to mesoscopic and macroscopic material properties essential to define the materiome. This chapter reviews large-scale atomistic and coarse-grain modeling methods commonly implemented to investigate the properties and behavior of natural and biological materials with nanostructured hierarchies. We present basic concepts of hierarchical multiscale modeling capable of providing a bottom-up description of chemically complex materials and some example applications related to the study of collagen material at different hierarchical levels.
Stabilization of UO2

Abstract Uranium dioxide, when exposed at elevated temperatures to an oxidizing atmosphere, will transform to U3O8. This compound exhibits appreciable vapour-pressure at temperatures in excess of 1200°C. The need for a stable high-temperature material requires prevention of the U3O8 transformation and, in certain applications, a lowering of the vapour-pressure. A method by which this may be accomplished is discussed. Solid-state studies of the uranium-lanthanum-oxygen (and the uranium-yttrium-oxygen) systems were conducted in the present investigation to elicit more detailed understanding of the factors involved. The oxidation and vaporization characteristics of uranium oxide were compared directly to those of solid solutions of uranium oxide containing up to approximately 60 mole per cent R2O3 additive, as La2O3 or Y2O3. These solid solutions, which have the fluorite structure, were formed by reacting UO2 and R2O3in vacuo. When these materials were oxidized, the fluorite structure was retained, with reduced lattice parameter. The volatile losses of solid solutions, as well as the oxidation state of the uranium, were found to vary inversely with the amount of the additive. Data are presented toward establishing: (a) lattice parameters and electrical characteristics of the “reduced” and “oxidized” solid solutions, (b) static weight losses of the oxides as a function of additive content, (c) the oxidation state of the uranium in the solid solutions, and (d) vapour-pressure results.
Democracy and Efficiency: Making Transition Towards an Empirical Approach

The relationship between democracy and efficiency has long been the interest of both economists and political scientists. However, no general consensus has been reached yet on this topic. There exist two schools of thought who has been pioneered this debate. According to Chicago school of thought, led by Gary Becker and Donald Wittman, democracy produces efficient results while Buchanan and Wagner (1977) and Olson (1982), of Virginia school of thought, think otherwise. However, their arguments for and against democracy was based on theoretical justification. In this paper, the author tries to address the question from purely an empirical point of view.
Identification of a galactose-like component of a chicken onco-developmental antigen

The chemical nature of one determinant (CFA 10) of a chicken onco-developmental antigen system was investigated using both chemical modification of cell surfaces and hapten inhibition. The presence of CFA 10 on pigeon RBC's is restricted both by the developmental status of the bird and by genetic segregation within the species. The involvement of a galactose-like structure with this determinant was suggested by the ability of alpha-galactosidase, sodium-m-periodate, and galactose oxidase to destroy CFA-10 activity. Other glycosidases including beta-galactosidase and proteolytic digestion failed to alter the antigenic determinant. Sugar inhibition assays using monospecific antisera against CFA 10 verified both the galactose-like specificity of the determinant and the possible significance of an alpha- vs. beta-internal linkage. It was possible to unmask cryptic CFA-10 sites on pigeon (10-) RBC's with use of specific glycosidases. While these cryptic sites also were susceptible to alpha-galactosidase, they may not be identical to the naturally exposed CFA 10 sites on pigeon (10+) RBC's. When pigeon (10-) RBC's were incubated in vitro with serum from 10+ pigeons, CFA 10 was detectable on the RBC surface. It is suggested that one mechanism of controlling the presence of CFA 10 on pigeon RBC's may be developmental changes in gene expression mediated through the serum environment.
Economic Implications of Variable Technology Standards for Optical Disc Piracy in a Global Context

Reduced sizes of music files due to compression technologies has allowed for piracy to become a rampant problem on the Internet even in the absence of significant bandwidth. However given the large sizes of video files, movies are still largely pirated by duplicating DVDs, VCDs and other physical media. Conventionally DVD formats have differed across various regions in the world albeit for controlling theatrical releases of movies. This paper formulates an analytical model to study the implication of varying technology standards of DVD players across different regions on the piracy of movies. This research identifies conditions under which consumers will engage in global and regional piracy. Our findings show that maintaining separate technology standards across regions is effective in not only thwarting global piracy but it also allows movie studios to create variable quality movies and engage in discriminatory pricing. While consumers may still engage in local piracy, the overall profits to the firm under variable technology standards are shown to be higher then when a common DVD standard is adopted across all regions. The paper concludes with recommendations for research and practice.
CHAPTER 47 – Structure of IFN-γ and Its Receptors

Interferon-y (IFN-γ) is a pleotropic cytokine that induces antiviral, antiproliferative, and immunomodulatory effects on numerous target cells. These diverse biological activities are initiated by IFN-γ-mediated aggregation of at least two different cell surface receptors: IFN-γR1 and IFN-γR2. X-ray crystallographic studies of IFN-γ and its receptors have been undertaken to delineate the molecular architecture of the receptor complexes and to understand the detailed recognition mechanisms that are ultimately responsible for IFN-γ biological responses. Here, these structures are summarized in the context of current biochemical and bioactivity data. Currently, the most intriguing model for IFN-γR2binding has been proposed from the analysis of the crystal structure of the IL-10/IL-10R1 complex. This structural model is supported by limited homolog scanning on IFN-γR1 and radiation inactivation data showing that IFN-γ biological activity requires two IFN-γ dimers. Confirmation of this model will require the structure determination of the IFN-γ/IFN-γR1/IFN-yR2 complex.
Nanoscale Elastic Changes in 2D Ti3C2Tx (MXene) Pseudocapacitive Electrodes

Designing sustainable electrodes for next generation energy storage devices relies on the understanding of their fundamental properties at the nanoscale, including the comprehension of ions insertion into the electrode and their interactions with the active material. One consequence of ion storage is the change in the electrode volume resulting in mechanical strain and stress that can strongly affect the cycle life. Therefore, it is important to understand the changes of dimensions and mechanical properties occurring during electrochemical reactions. While the characterization of mechanical properties via macroscopic measurements is well documented, in situ characterization of their evolution has never been achieved at the nanoscale. It is reported here with in situ imaging, combined with density functional theory of the elastic changes of a 2D titanium carbide (Ti3C2Tx) based electrode in direction normal to the basal plane (electrode surface) during alkaline cation intercalation/extraction. 2D carbides, known as MXenes, are promising new materials for supercapacitors and various kinds of batteries, and understanding the coupling between their mechanical and electrochemical properties is therefore necessary. The results show a strong correlation between the cations content and the out-of-plane elastic modulus. This strategy enables identifying the preferential intercalation pathways within a single particle, which is important for understanding ionic transport in these materials.
The value of clumping to prey : Experiments with a mammalian predator.

Southern grasshopper mice (Onychomys torridus) were allowed to junt buried mealworms in a laboratory arena. The prey were arranged in two patterns, one aggregated and one relatively dispersed. Mice captured more prey from the dispersed treatment in the 2 h experiment, a result that can be attributed to both the greater ease of finding the first prey and a more efficient style of search for dispersed prey.
Asthma and Aging

Although the current prevalence of asthma in elderly individuals may be comparable to the general population, the increase in size of this population will likely cause the asthma burden to increase in the next few decades. Asthma in older adults is often under-diagnosed and under-treated. Furthermore, there is no uniform consensus in defining its clinical and physiologic characteristics and little is known about the pathophysiologic mechanisms of asthma in this age group. In general, two phenotypes of asthma in the elderly have been described; one that is secondary to persistence of childhood asthma, called “long-standing asthma (LSA)”, and the other which develops later in life, termed “late onset asthma (LOA)”. Immune mechanisms, environmental triggers and genetic factors are important determinants for the development of asthma, but their role in the pathogenesis of late onset asthma and persistence of asthma into later ages, is less certain. Respiratory infections may play a more important role than allergic mechanisms in the development of LOA. In addition, chronic airway inflammation, a characteristic finding in asthma, may be different in older adults compared to the younger population. These differences in risk factors, triggers and pathophysiologic mechanisms in the elderly with asthma coupled with physiologic factors related to the aging lung and increased incidence of comorbidities emphasize the need for a unique approach to the diagnosis, assessment and management of asthma in this population.
THE FUNCTION OF CALL ALTERNATION IN ANURAN AMPHIBIANS: A TEST OF THREE HYPOTHESES.

Males of many species of anurans alternate calls with those of their neighbors in a chorus. This pattern of calling reduces signal interference and may: 1) facilitate intermale spacing because males can better gauge the intensity of neighbors' calls if these calls do not overlap with their own; 2) help preserve species-specific temporal information in calls required to attract females; and/or 3) make it easier for females to localize males in the chorus. I tested these hypotheses with three species that exhibit call alternation, Hyla crucifer, H. versicolor, and H. microcephala. Males of all three species gave more aggressive calls to high-intensity synthetic stimuli that alternated with their calls than to those that overlapped their calls. These results support the first hypothesis. Results of four-speaker female choice experiments using alternating and overlapping calls indicate that preservation of signal integrity also is important in H. versicolor and H. microcephala, species that have fine-scale temporal information in their calls. However, the third hypothesis was not supported; females failed to discriminate among alternating and overlapping calls if the problem of signal disruption was eliminated or irrelevant.
Drainage Evolution and Fish Dispersal in the Central Appalachians

The study of fish dispersal in the central Appalachians is a perplexing problem to ichthyologists who often must rely on geological literature to determine past drainage relationships. Many classical geomorphological treatments of drainage history and evolution are often dated (1884–1934), and controversial as well. Biogeographers sometimes make conjectures about past drainage relationships on the basis of present species distributional patterns even though complementary geological data are lacking. In view of that, it has been stressed that Zoogeographic conclusions regarding past drainage patterns are best based on facts supported by a combination of geological and biological evidence (Hack, 1969; Ross, 1969). Stream piracy (or capture) is a mode, of drainage rearrangement and divide migration that may be initiated from various geological processes—for example, uplift, faulting, glaciation, folding, volcanic activity, and the like. In a capture, an entire section of stream may be diverted from one drainage to another. Physical features that frequently contribute to this phenomenon are a combination of steeper gradient, softer substrate, higher discharge, and lower elevation of the pirate stream (Bonnett, 1977). Geological criteria for establishing a stream piracy include elbows of capture, barbed tributaries, abandoned channels, wind gaps, and large valleys occupied by small streams. With a piracy, intradrainage or interdrainage transfer of biota is facilitated. However, it is expected that the pirate stream receives more species from the captor than it delivers (Jenkins and others, 1972), unless the fauna of the captured stream is depauperate. Efficiency of faunal dispersal may be related to the physical conditions associated with stream captures and the amount of time the pirate and captive streams are in contact.
A Robust Ni(II) α-Diimine Catalyst for High Temperature Ethylene Polymerization

Sterically demanding NiII α-diimine precatalysts were synthesized utilizing 2,6-bis(diphenylmethyl)-4-methyl aniline. When activated with methylaluminoxane, the catalyst NiBr2(ArN═C(Me)–C(Me)═NAr) (Ar = 2,6 bis(diphenylmethyl)-4-methylbenzene) was highly active, produced well-defined polyethylene at temperatures up to 100 °C (Mw/Mn = 1.09–1.46), and demonstrated remarkable thermal stability at temperatures appropriate for industrially used gas-phase polymerizations (80–100 °C).
Cell-mediated complementation of human adenoviruses by simian papovavirus.

SummaryAlthough SV40 can replicate well in certain stable cell lines of GMK cells, some of the infected cultures do not support the complementation of the human adenovirus 7. Maximum complementation occurred only in the primary cells although consistent complementation at a lower level was detected in CV-1 cells. No complementation occurred in Vero cells and little, if any, was detected in BSC-1 cells. Therefore, the host cell has a role in determining the interaction of these two viruses and conditions other than those necessary for the efficient replication of SV40 must be present for the complementation of the human adenoviruses in simian cells.We thank Beverly Poole for helping with these studies.
An experimental and angiographic explanation of why ulcerated carotid bulbs embolize.

The flow dynamics and pressure relationships in an ulcerated atherosclerotic carotid bulb obtained at post-mortem were studied and correlated with angiographic findings in a similar live patient. Using the lost wax technique, we created replicas of an ulcerated atherosclerotic carotid bulb from a fresh cadaver; and placed those replicas in a circuit of pulsating non-Newtonian fluid. Flow profiles were adjusted to replicate human physiologic flows, and flow rates of400, 600, and 800 milliliters per minute were evaluated. In the replicas, the slipstreams were opacified with isobaric dyes, and images were recorded both on 35 mm film and on SuperVHS high speed video. Data were collected from needles placed radially in the common carotid artery, in the region of the maximal atherosclerotic narrowing, and in the internal carotid artery. Though pressure relationships could not be obtained in the live human for ethical reasons, angiography in a similar stenosis was evaluated for slipstream dynamics. The post-mortem replica had a 55% diameter stenosis (88% area stenosis) of the carotid bulb with a shallow 3 mm ulcer. Flow in the common carotid artery showed undisturbed slipstreams, but as these slipstreams entered the narrow bulb, they crowded together, accelerating dramatically, with a jet continuing distally beyond the maximal narrowing for at least 2 vessel diameters, where flow again became normal. As fluid entered the narrowed bulb, radial pressures decreased and within the ulcer a vortex circulation was found. Similar findings were observed on the angiographic images of the live patient. This combination of events, the slowly swirling fluid in the ulcer, which would allow platelet aggregates to form, and the intermittent low pressure of the Bernoulli effect which could pull the aggregates into the adjacent rapidly flowing blood may help explain how ulcerated carotid plaques lead to embolic stroke.
Understanding Ebola: the 2014 epidemic

Near the end of 2013, an outbreak of Zaire ebolavirus (EBOV) began in Guinea, subsequently spreading to neighboring Liberia and Sierra Leone. As this epidemic grew, important public health questions emerged about how and why this outbreak was so different from previous episodes. This review provides a synthetic synopsis of the 2014–15 outbreak, with the aim of understanding its unprecedented spread. We present a summary of the history of previous epidemics, describe the structure and genetics of the ebolavirus, and review our current understanding of viral vectors and the latest treatment practices. We conclude with an analysis of the public health challenges epidemic responders faced and some of the lessons that could be applied to future outbreaks of Ebola or other viruses.
Spatially resolved microfluidic stimulation of lymphoid tissue ex vivo

The lymph node is a structurally complex organ of the immune system, whose dynamic cellular arrangements are thought to control much of human health. Currently, no methods exist to precisely stimulate substructures within the lymph node or analyze local stimulus-response behaviors, making it difficult to rationally design therapies for inflammatory disease. Here we describe a novel integration of live lymph node slices with a microfluidic system for local stimulation. Slices maintained the cellular organization of the lymph node while making its core experimentally accessible. The 3-layer polydimethylsiloxane device consisted of a perfusion chamber stacked atop stimulation ports fed by underlying microfluidic channels. Fluorescent dextrans similar in size to common proteins, 40 and 70 kDa, were delivered to live lymph node slices with 284 ± 9 μm and 202 ± 15 μm spatial resolution, respectively, after 5 s, which is sufficient to target functional zones of the lymph node. The spread and quantity of stimulation were controlled by varying the flow rates of delivery; these were predictable using a computational model of isotropic diffusion and convection through the tissue. Delivery to two separate regions simultaneously was demonstrated, to mimic complex intercellular signaling. Delivery of a model therapeutic, glucose-conjugated albumin, to specific regions of the lymph node indicated that retention of the drug was greater in the B-cell zone than in the T-cell zone. Together, this work provides a novel platform, the lymph node slice-on-a-chip, to target and study local events in the lymph node and to inform the development of new immunotherapeutics.
An audit of retail beef loin steak tenderness conducted in eight U.S. cities.

An audit of supermarkets in eight U.S. cities was conducted to characterize retail beef loin steaks with respect to grade, postfabrication aging, and tenderness and to provide an interim measure of progress in industry efforts to improve retail beef tenderness. Top sirloin steaks (n = 819) and strip loin steaks (n = 827 paired steaks) were purchased at retail markets in Atlanta, Chicago, Denver, Houston, Philadelphia, Phoenix, San Francisco, and Seattle and shipped to Colorado State University for measurement of shear force (both cut types) and evaluation by a trained sensory panel (strip loins only). Approximately 80% of the steaks originated from beef plants in Kansas, Texas, Nebraska, and Colorado. Postfabrication aging periods ranged from 2 to 87 d (mean = 20.8 d) for top sirloin steaks and from 2 to 91 d (mean = 19.2 d) for strip loin steaks, although most top sirloin (85%) and strip loin (91%) steaks were available for purchase 7 to 35 d after fabrication. The mix of quality grades was similar for both cuts: 60% Select, 31% "commodity" Choice, 6 to 7% "Certified" Choice, and 2 to 3% Prime. Shear force averaged 3.46 kg (SD = .74) for top sirloins and 3.05 kg (SD = .95) for strip loins; 75% of both steak types had shear force values between 2 and 4 kg. Postfabrication periods shorter than 7 d were associated with reduced (P Choice > Select) for both cuts. Based on panel tenderness ratings, the approximate odds of obtaining a "slightly tough" or tougher strip loin steak at a retail supermarket were: 0 for Prime, 1 in 10 for "Certified" Choice, 1 in 5 for "commodity" Choice, and 1 in 4 for Select. Audit results suggest that tenderness characteristics of loin steaks have not changed materially since the National Beef Tenderness Survey was conducted in 1991 and that two primary focal points of the beef industry's efforts to improve tenderness should be 1) to prevent short-aged (< 7 d postfabrication) product from reaching consumers and 2) to identify methods for enhancing tenderness of Select and "commodity" Choice beef.
Cerebrovascular Complications of Cardiac Surgery

Abstract Cardiac surgery has undergone a rapid and extraordinary development since mid-1940s. Many operations that were once considered experimental are now commonplace, with thousands of open heart procedures performed annually in the United States. As of 2016, an estimated 1 million patients undergo cardiac surgery throughout the world every year. Neurological impairment is a well-known complication of cardiac surgery, resulting in longer hospitalizations, increased costs, and an escalation in morbidity and mortality. The types of neurological complications vary and can include peripheral neuropathy, encephalopathy, cognitive impairment, and stroke. Overall, in prospective studies, transient neurological complications have been noted in 61% of cardiac surgery patients. Although refinements in surgical and anesthesia techniques have improved neurological outcomes, the number of elderly patients undergoing cardiac surgery has also increased, and thus cerebrovascular complications in particular continue to occur.
Assessing the viscoelasticity of chicken liver by OCE and a Rayleigh wave model

This study investigates the feasibility of quantifying the viscoelasticity of soft tissues with a dynamic noncontact optical coherence elastography (OCE) technique coupled with a Rayleigh wave model. Spectral analysis of an air-pulse induced elastic wave as measured by OCE provided the elastic wave dispersion curve. The dispersion curve was fitted to an analytical solution of the Rayleigh wave model to determine the Young’s modulus and shear viscosity of samples. In order to validate the method, 10% gelatin phantoms with and without different concentrations of oil were prepared and tested by OCE and mechanical testing. Results demonstrated that the elasticities as assessed by the Rayleigh wave model generally agreed well with mechanical testing, and that the viscosity in the phantom with oil samples was higher than the phantoms without oil, which is in agreement with the literature. Further, this method was applied to quantify the viscoelasticity of chicken liver. The Young’s modulus was E=2.04±0.88 kPa and the shear viscosity was η=1.20±0.13 Pa·s with R2=0.96±0.04 between the OCE-measured dispersion curve and Rayleigh wave model analytical solution. Combining OCE and the Rayleigh wave model shows promise as an effective tool for noninvasively quantifying the viscoelasticity of soft tissues.
Pregnancy After Bariatric Surgery: National Survey of Obstetrician’s Comfort, Knowledge, and Practice Patterns

The objective of this study is to survey a nationally representative sample of obstetricians regarding comfort, knowledge, and practice patterns of caring for pregnant women after bariatric surgery. We conducted an online survey of US obstetricians and describe obstetrician’s demographics, practice settings, and practice patterns. We assessed respondent’s knowledge and recommended practices. We compared provider knowledge by years since completing residency, scope of practice (generalist or specialist), and practice setting (academic setting or other). Statistical significance was set at p < 0.05. A total of 106 completed the survey (response rate of 54%). Respondents had a median age of 47 and median 17 years in practice. Sixty-two percent were generalists. Nearly all of the respondents (94%) had some experience with caring for pregnant women after bariatric surgery and 83% reported feeling “very comfortable” (48%) or “somewhat comfortable” (35%) providing care for this population. Most (74%) were aware of increased risk of small for gestational age after surgery. Only 13% were able to correctly identify all recommended nutritional labs and 20% reported that they “did not know” which labs are recommended. There were no differences in comfort, experience, knowledge, and practice patterns by physician characteristics and practice settings. While most obstetricians are aware of perinatal risks after bariatric surgery, a substantial percentage of obstetricians are unaware of recommended practices regarding nutrition and nutritional monitoring. As bariatric surgery becomes increasingly prevalent among reproductive age women, educational interventions to increase obstetricians’ knowledge of optimal care of pregnant women after bariatric surgery are urgently needed.
Updated Outcomes of Early Endoscopic Realignment for Pelvic Fracture Urethral Injuries at a Level 1 Trauma Center

Objective To present our updated experience and discuss potential benefits of early endoscopic realignment (EER) for patients with pelvic fracture urethral injuries (PFUIs). Methods A retrospective review of patients treated with EER after blunt PFUIs was performed. EER was performed with a retrograde or a combined antegrade or retrograde approach with a cystoscope. Treatment success was defined as no secondary procedure or the ability to pass a cystoscope across the area of injury or surgical anastomosis. Results Thirty-two patients (mean age 38 years, range 17-73) underwent EER between 2004 and 2016 with a mean follow-up of 26 months (range 1-102). Median time to realignment was 2 days (range 0-6) and was performed concomitantly with another surgical service in 72% of cases. Median operative time for EER was 38 minutes (range 8-100). Using an intent-to-treat analysis, 29 patients (91%) failed EER. Nine patients underwent a subsequent endoscopic procedure with 22% success rate. Excision and primary anastomotic urethroplasty was performed in 24 patients as a primary or secondary treatment with 96% success rate. Conclusion Our overall success rate for EER was 9%, but did not hinder subsequent urethroplasty success. The decision for performing EER should not be based on success alone. Secondary benefits of EER exist and may assist with the multidisciplinary care of a patient with complex trauma. The management of PFUI is challenging and these patients should be referred to tertiary centers.
The state of race and punishment in America: Is justice really blind?

Abstract Purpose The study of racial disparity in the formal application of punishment (i.e., criminal sentencing) is widely recognized as an important area of research. Hundreds of studies have weighed in to determine whether race influences sentence outcomes (e.g., imprisonment and sentence length) and the current work attempts to summarize key aspects of this expansive literature. Methods The present assessment relies on 1) prior reviews of the race/sentencing literature and 2) the latest research published since the year 2010 to answer a series of important questions about the race/sentencing relationship. Results The preponderance of evidence indicates that race and ethnicity often play a small to moderate role in key sentence outcomes. Relative to white offenders, those who are African American, Latina/o, and Native American often receive harsher sentences, while those who are Asian often receive similar or more lenient sentences. These findings, however, are not universal and tend to be context specific. Conclusion The process of criminal sentencing strives for race neutrality but does not always achieve this goal.