bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rate and Synchrony in Feedforward Networks of Coincidence Detectors: Analytical Solution
Authors: Mikula Shawn , Niebur Ernst 
Published: March 2005

We provide an analytical recurrent solution for the firing rates and cross-correlations of feedforward networks with arbitrary connectivity, excitatory or inhibitory, in response to steady-state spiking input to all neurons in the first network layer. Connections can go between any two layers as long as no loops are produced. Mean firing rates and pairwise cross-correlations of all input neurons can be chosen individually. We apply this method to study the propagation of rate and synchrony information through sample networks to address the current debate regarding the efficacy of rate codes versus temporal codes. Our results from applying the network solution to several examples support the following conclusions: (1) differential propagation efficacy of rate and synchrony to higher layers of a feedforward network is dependent on both network and input parameters, and (2) previous modeling and simulation studies exclusively supporting either rate or temporal coding must be reconsidered within the limited range of network and input parameters used. Our exact, analytical solution for feedforward networks of coincidence detectors should prove useful for further elucidating the efficacy and differential roles of rate and temporal codes in terms of different network and input parameter ranges.
Patient Adherence Improves Glycemic Control
Authors: Rhee Mary K. , Slocum Wrenn , Ziemer David C. , Culler Steven D. , Cook Curtiss B. , El-Kebbi Imad M. , Gallina Daniel L. , Barnes Catherine , Phillips Lawrence S. 
Published: March 2005

Purpose The purpose of this study was to assess the influence of appointment keeping and medication adherence on HbA1c. Methods A retrospective evaluation was performed in 1560 patients with type 2 diabetes who presented for a new visit to the Grady Diabetes Clinic between 1991 and 2001 and returned for a follow-up visit and HbA1c after 1 year of care. Appointment keeping was assessed by the number of scheduled intervening visits that were kept, and medication adherence was assessed by the percentage of visits in which self-reported diabetes medication use was as recommended at the preceding visit. Results The patients had an average age of 55 years, body mass index (BMI) of 32 kg/m2, diabetes duration of 4.6 years, and baseline HbA1c of 9.1%. Ninety percent were African American, and 63% were female. Those who kept more intervening appointments had lower HbA1c levels after 12 months of care (7.6% with 6-7 intervening visits vs 9.7% with 0 intervening visits). Better medication adherence was also associated with lower HbA1c levels after 12 months of care (7.8% with 76%-100% adherence). After adjusting for age, gender, race, BMI, diabetes duration, and diabetes therapy in multivariate linear regression analysis, the benefits of appointment keeping and medication adherence remained significant and contributed independently; the HbA1c was 0.12% lower for every additional intervening appointment that was kept (P= .0001) and 0.34% lower for each quartile of better medication adherence (P= .0009). Conclusion Keeping more appointments and taking diabetes medications as directed were associated with substantial improvements in HbA1c. Efforts to enhance glycemic outcomes should include emphasis on these simple but critically important aspects of patient adherence.
Implementing the Chronic Care Model for Improvements in Diabetes Care and Education in a Rural Primary Care Practice
Authors: Siminerio Linda M. , Piatt Gretchen , Zgibor Janice C. 
Published: March 2005

Purpose The purpose of this pilot study was to determine the impact of implementing elements of the chronic care model (CCM; decision support, self-management, and delivery system redesign) on providers' diabetes care practices and patient outcomes in a rural practice setting. Methods In this pilot study, 104 patients with type 2 diabetes and 6 providers in a rural primary care practice were involved in an intervention that included a certified diabetes educator (CDE) who educated and supported providers on diabetes management and adherence to the American Diabetes Association (ADA) Standards of Care over the year of the project. The CDE also provided diabetes self-management education (DSME) at the office site for 29 of the 104 patients who received their care in the practice. The following variables were evaluated: provider perceived barriers to care and adherence to ADA standards of care and patient A1C, blood pressure, cholesterol, knowledge, and empowerment levels. Results Provider adherence to ADA Standards of Care increased significantly across all process measures. Patients who received DSME at point of service in the primary care practice setting gained improvements in knowledge, empowerment, A1C, and high-density lipoprotein cholesterol levels. Conclusions Implementing systems to support decision support, selfmanagement education, and delivery system redesign has a positive influence on practices and patient outcomes in outlying rural communities.
Barriers to A1C Testing Among a Managed Care Population
Authors: Delaronde Steven 
Published: March 2005

Purpose The purpose of this study is to explore reasons adults with diabetes do not receive at least 2 A1C tests per year as recommended by the American Diabetes Association (ADA). Methods ConnectiCare, a regional managed care company based in Farmington, Connecticut, identified adult members with diabetes who did not have a medical claim for an A1C laboratory test from their physician. A questionnaire was sent to 740 randomly selected members asking them to report the number of A1C tests they received in the past 12 months and reasons for not receiving the number of tests recommended by the ADA. After sending an automated telephone reminder to nonrespondents, a 26% (n = 192) response rate was achieved. Results Thirty-three percent of respondents (n = 63) reported having diabetes and receiving fewer than 2 A1C tests in the past year. Respondents were equally divided between men and women, with a mean age of 58 years. The primary reasons given for not obtaining at least 2 A1C tests as recommended by the ADA were that respondents were unaware that the test is recommended (49%), not informed of the need for the test by their physician (38%), never heard of the A1C test (33%), and not seen regularly by their physician (19%). Conclusions Diabetes self-management education remains an important means of encouraging adherence to important ADA recommendations such as regular A1C testing. Barriers to A1C testing can be addressed in multiple settings, including individual and group education, disease management programs, and physician education.
Recruitment and Retention of Rural African Americans in Diabetes Research
Authors: Loftin Wanda Anderson , Barnett Steven K. , Bunn Peggy Summers , Sullivan Patra 
Published: March 2005

Purpose The purpose of this article was to describe lessons learned about recruitment and retention of rural African Americans from published literature, the authors’ research, and research experience. Two rural, communitybased research studies with African Americans with diabetes are used to illustrate different issues and strategies in recruitment and retention. Methods Relevant MEDLINE articles and clinical studies were reviewed, and the design, implementation, and results of the 2 community-based studies were evaluated. Information from the literature, research results, and sample selection, participation, and attrition experiences were synthesized to determine effective approaches for recruitment and retention. Results Research funding, design, and implementation; recruitment methods; culturally competent approaches; caring, trusting provider-patient relationships; incentives; follow-up; and factors in the rural environment emerged as important issues influencing recruitment and retention. Conclusion Recruitment and retention of African Americans in rural diabetes research is a significant challenge, and adequate funding should be sought early in the research process. Culturally competent approaches; caring, trusting relationships; incentives; and follow-up are important concepts in successful recruitment, participation, and retention of African Americans. The lessons learned may be applicable to the more widespread issue of recruitment and retention of rural African Americans in diabetes education programs.
Central pattern generator for swimming in Melibe
Authors: Thompson Stuart , Watson Winsor H. 
Published: March 2005

SUMMARY
The nudibranch mollusc Melibe leonina swims by bending from side to side. We have identified a network of neurons that appears to constitute the central pattern generator (CPG) for this locomotor behavior, one of only a few such networks to be described in cellular detail. The network consists of two pairs of interneurons, termed `swim interneuron 1' (sint1) and`swim interneuron 2' (sint2), arranged around a plane of bilateral symmetry. Interneurons on one side of the brain, which includes the paired cerebral, pleural and pedal ganglia, coordinate bending movements toward the same side and communicate via non-rectifying electrical synapses. Interneurons on opposite sides of the brain coordinate antagonistic movements and communicate over mutually inhibitory synaptic pathways. Several criteria were used to identify members of the swim CPG, the most important being the ability to shift the phase of swimming behavior in a quantitative fashion by briefly altering the firing pattern of an individual neuron. Strong depolarization of any of the interneurons produces an ipsilateral swimming movement during which the several components of the motor act occur in sequence. Strong hyperpolarization causes swimming to stop and leaves the animal contracted to the opposite side for the duration of the hyperpolarization. The four swim interneurons make appropriate synaptic connections with motoneurons, exciting synergists and inhibiting antagonists. Finally, these are the only neurons that were found to have this set of properties in spite of concerted efforts to sample widely in the Melibe CNS. This led us to conclude that these four cells constitute the CPG for swimming. While sint1 and sint2 work together during swimming, they play different roles in the generation of other behaviors. Sint1 is normally silent when the animal is crawling on a surface but it depolarizes and begins to fire in strong bursts once the foot is dislodged and the animal begins to swim. Sint2 also fires in bursts during swimming, but it is not silent in non-swimming animals. Instead activity in sint2 is correlated with turning movements as the animal crawls on a surface. This suggests that the Melibe motor system is organized in a hierarchy and that the alternating movements characteristic of swimming emerge when activity in sint1 and sint2 is bound together.
Undetectable apolipoproteinA-Igene expression suggests an unusual mechanism of dietary lipid mobilisation in the intestine ofCyprinus carpio
Authors: Concha Margarita I. , López Rodrigo , Villanueva Julieta , Báez Nadya , Amthauer Rodolfo 
Published: March 2005

SUMMARYHigh density lipoprotein (HDL) has been shown to play an important role in the dietary lipid mobilisation in the carp. In spite of this, previous studies have failed to demonstrate the synthesis of the major protein component of HDL, apolipoprotein A-I (apoA-I), in the proximal intestine of the carp. Therefore, the aim of the present study was to evaluate the expression of apoA-I throughout the entire intestine. Curiously, no transcription of the apoA-I gene could be detected either by northern blot or RT–PCR assays in the intestinal mucosa, in clear contrast with the abundant cytosolic immunoreactive apoA-I detected in almost all intestinal segments, which suggests a different origin for this protein. In addition, the detection of specific, but low affinity, binding sites for apoA-I in the carp intestinal brush-border membranes (BBM), and the strong interaction with BBM, which is highly dependent on temperature, points to an important contribution of membrane lipids in apoA-I binding to the intestinal mucosa. This idea was reinforced by the ability of carp apoA-I to associate with multilamellar phospholipid vesicles.
Respiratory changes throughout ontogeny in the tobacco hornworm caterpillar,Manduca sexta
Authors: Greenlee Kendra J. , Harrison Jon F. 
Published: March 2005

SUMMARYThe respiratory system of growing caterpillars is challenged in two distinct ways as they develop from hatchlings to fifth instars preparing for pupation. First, across instars, body sizes and tracheal lengths increase substantially. Second, within each instar, animal mass can more than double while major tracheal respiratory system structures, such as spiracles and large tracheae, are fixed in size until molting. To test whether these growth processes result in a decrease in O2 delivery capacity relative to tissue oxygen needs, we exposed feeding Manduca sexta larvae of various ages to decreasing levels of atmospheric O2 and measured their metabolic rate and ability to feed. We found that near the beginning of all instars, M. sexta were able to maintain gas exchange and feed down to approximately 5 kPa O2, indicating that these insects are able to match tracheal O2 delivery to increased metabolic rates across instars. However, gas exchange and feeding of caterpillars nearing the molt were limited at much higher O2 levels (up to 15 kPa O2), suggesting that caterpillars have limited capacities to increase tracheal O2 delivery as O2 consumption rates increase within instars. It seems possible that the safety margin for O2 delivery may disappear completely in the last hours before ecdysis, providing an ultimate if not proximate explanation for the necessity of molting.
Oxygen and water flux across eggshells ofManduca sexta
Authors: Woods H. Arthur , Bonnecaze Roger T. , Zrubek Brandy 
Published: March 2005

SUMMARYInsect eggs must obtain oxygen across the eggshell to support embryonic development. Because eggs are small, obtaining enough oxygen would seem trivial. Recent work, however, has shown that eggs of a moth, Manduca sexta, are oxygen limited at high but realistic temperatures(32–37°C) and that PO2 drops steeply across the eggshell. Here we use theoretical and experimental approaches to partition the total resistance to oxygen flux among several steps in the oxygen cascade from environment to embryo. Standard mass-transfer analysis suggests that boundary layers of air around eggs, and around substrates to which they are attached, offer negligible resistance. Likewise, a mathematical model, parameterized using published and newly obtained morphological data,predicts that air-filled parts of the chorion also do not resist oxygen flux. This prediction was confirmed by experiments that measured rates of carbon dioxide emission from batches of eggs subjected simultaneously to hypoxia and inert gas substitution: depression of metabolic rate by hypoxia was not rescued when the diffusion coefficient of oxygen in air was doubled by substituting helium for nitrogen. The model did predict, however, that a set of subchoral layers (a crystalline chorionic layer, a wax layer and the vitelline membrane) could account for most or all of the total resistance to oxygen flux. Support for this prediction was obtained from two sequential experiments. First, eggs extracted with chloroform:methanol had highly elevated rates of water loss, suggesting that indeed eggs of M. sextaare waterproofed by wax. Second, rates of water loss and carbon dioxide emission from batches of eggs, measured from laying to hatching, changed in parallel over development. These data suggest that a single layer, likely a wax layer or a combination of wax and other subchoral layers, provides the main resistance to water efflux and oxygen influx.
The mechanics of sound production inPanacanthus pallicornis(Orthoptera: Tettigoniidae: Conocephalinae): the stridulatory motor patterns
Authors: Montealegre-Z Fernando , Mason Andrew C. 
Published: March 2005

SUMMARYTo examine whether sound production in katydids relies on an escapement mechanism similar to that of crickets we investigated the functional anatomy and mechanical properties of the stridulatory apparatus in the katydid Panacanthus pallicornis. Males of this species produce sustained pulses with a sharp low frequency peak of ∼5 kHz and a broad band spectrum between 15 and 25 kHz. Simultaneous recordings of movement and sound indicate that the entire stridulatory file is used for sound production and there is nearly a 1:1 correspondence between the number of cycles in a song and the number of teeth on the file. There is an overall tendency for both the spacing of teeth to increase along the file and the velocity of wing closure to increase as the scraper traverses the file. There is considerable variation,however, in the evenness of tooth spacing and in the instantaneous velocity of wing closure during sound production. The production of sustained pulses appears to depend on resonance in the right tegmen, with the left tegmen acting primarily as a damping element. This resonance is not strongly coupled to the scraper and, unlike crickets, the timing of file-scraper interactions,and therefore the phasing of energy input to wing oscillations, is variable. Similarly, the quality of the sound spectrum varies over the course of a single stridulatory wing-stroke. Based on measurements of tooth spacing on the stridulatory file and cycle-by-cycle frequency of sound output, we predicted the velocity of wing movement that would provide consistent phasing of file-scraper interactions with respect to sound-radiating wing oscillations and compared this with measurements of wing velocity. Acceleration of wing velocity during stridulation results in a closer match to the velocity required for optimal phasing during a portion of the call, and this corresponds with higher amplitudes of radiated sound and the excitation of higher order modes of vibration (evident as distinct harmonic peaks in spectrograms). Our results suggest that in katydid stridulation, the movement of the scraper along the file is not regulated by an escapement mechanism as it is in crickets. Instead, katydids that produce pure-tone songs sweep their wings over a range of velocities, within which some portion matches file tooth spacing to give optimal phasing of energy input to excite a resonance in the right tegmen.
Echolocation call intensity in the aerial hawking batEptesicus bottae(Vespertilionidae) studied using stereo videogrammetry
Authors: Holderied Marc W. , Korine Carmi , Fenton M. Brock , Parsons Stuart , Robson Stuart , Jones Gareth 
Published: March 2005

SUMMARYAerial hawking bats use intense echolocation calls to search for insect prey. Their calls have evolved into the most intense airborne animal vocalisations. Yet our knowledge about call intensities in the field is restricted to a small number of species. We describe a novel stereo videogrammetry method used to study flight and echolocation behaviour, and to measure call source levels of the aerial hawking bat Eptesicus bottae(Vespertilionidae). Bats flew close to their predicted minimum power speed. Source level increased with call duration; the loudest call of E. bottae was at 133 dB peSPL. The calculated maximum detection distance for large flying objects (e.g. large prey, conspecifics) was up to 21 m. The corresponding maximum echo delay is almost exactly the duration of one wing beat in E. bottae and this also is its preferred pulse interval. These results, obtained by using videogrammetry to track bats in the field,corroborate earlier findings from other species from acoustic tracking methods.
Androgen control of immunocompetence in the male house finch,Carpodacus mexicanusMüller
Authors: Deviche Pierre , Cortez Luis 
Published: March 2005

SUMMARYThe immunocompetence handicap (ICH) hypothesis predicts that elevated levels of the gonadal androgen testosterone (T) entail obligatory costs, such as immunosuppression, but evidence supporting this immunosuppressive influence is equivocal. To investigate this question, adult males house finches, Carpodacus mexicanus, were exposed to short days and chronically treated with T-filled (T males; N=10) or empty (C males; N=10) Silastic capsules. Testosterone administration increased plasma T levels and the size of the cloacal protuberance, an androgen-dependent secondary sexual characteristic. To study humoral immunity, finches received injections of sheep red blood cells (SRBC) and we measured circulating concentrations of antibodies to these cells with a hemagglutination test. All males produced antibodies following four SRBC injections at weekly intervals. Antibody titers in T and C males did not differ 5 days after the fourth injection, but were 59% lower in T than C males 2 weeks later. To study cell-mediated immunity, we measured the local inflammatory response to an injection of phytohemaglutinin (PHA). This response in T and C males was similar 1 day after PHA injection, but was 58% less in T than C males 2 days following the injection. Thus, T and C males mounted similar humoral and cell-mediated immune responses, but T treatment compromised maintenance of these responses. The results, demonstrating immunosuppressive effects of elevated T, are consistent with the ICH hypothesis.
Temporal and spatial changes in the expression pattern of multiple red and green subtype opsin genes during zebrafish development
Authors: Takechi Masaki , Kawamura Shoji 
Published: March 2005

SUMMARY
Zebrafish have two red, LWS-1 and LWS-2, and four green, RH2-1, RH2-2, RH2-3 and RH2-4, opsin genes encoding photopigments with distinct absorption spectra. Occurrence of opsin subtypes by gene duplication is characteristic of fish but little is known whether the subtypes are expressed differently in the retina, either spatially or temporally. Here we show by in situ hybridization the dynamic expression patterns of the opsin subtypes in the zebrafish retina. Expression of red type opsins is initiated with the shorter-wavelength subtype LWS-2, followed by the longer-wavelength subtype LWS-1. In the adult retina, LWS-2 was expressed in the central to dorsal area and LWS-1 in the ventral and peripheral areas. Expression patterns of green type opsins were similar to those of the red type opsins. The expression started with the shortest wavelength subtype RH2-1 followed by the longer wavelength ones, and in the adult retina, the shorter wavelength subtypes (RH2-1 and RH2-2) were expressed in the central to dorsal area and longer wavelength subtypes (RH2-3 and RH2-4)in the ventral and peripheral areas. These results provide the framework for subsequent studies of opsin gene regulation and for probing functional rationale of the developmental changes by using the power of zebrafish genetics.