Are recently developed rodent models of binge eating also models of food addiction? Valid models should meet human criteria for both bingeing and substance dependence as described in the 4th edition ...and proposed for the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM). Similarly, behavioral profiles of bingeing animals should share characteristics with those of animal models of drug addiction. We evaluate and discuss current rodent models of bingeing, their contributions to scientific understanding of bingeing, their validity with respect to DSM criteria, and their overlap with models of addiction. The models described indicate that repeated intermittent bouts in which large quantities of fatty or sugary foods are consumed (binges) are associated with behavioral changes similar to those described for drugs of abuse. In contrast, control groups consuming the same foods in a nonbinge-type manner do not exhibit an "addiction-like" behavioral profile. Thus, fatty/sugary foods in and of themselves do not appear to have addictive qualities. Rather, the manner in which they are consumed appears to be critical. In addition, while rodent models of bingeing and drug self-administration share similarities, we do not support reclassifying the bingeing-related eating disorders as substance use disorders because of differences that distinguish such disorders in humans.
This study assessed the effects of the opioid antagonist naltrexone, the dopamine 2-like (D2) antagonist raclopride, and the GABA
B agonist baclofen on consumption of fat/sucrose mixtures (FSM) using ...a limited access protocol. Sixty male Sprague-Dawley rats were grouped according to two schedules of access (Daily D or Intermittent I) to an optional FSM. Each FSM was created by whipping 3.2% (L), 10% (M), or 32% (H) powdered sugar into 100% vegetable shortening in a w/w manner (
n
=
10 per group). One-hour intakes of the IL and IM groups were significantly greater than intakes of the respective DL and DM groups, thus fulfilling our operational definition of binge-type eating in these groups. Baclofen reduced intakes of the L and M mixtures regardless of access schedule, but failed to reduce intake of the H mixture. Naltrexone reduced intake in all groups, but potency was greater in IL rats than in DL rats. Furthermore, potency was attenuated in Intermittent rats, but enhanced in Daily rats, at higher sucrose concentrations. Raclopride reduced intake in the DL and stimulated intake in the IL groups, reduced intake in both M groups, and was without effect in both H groups. These results indicate that fat/sucrose mixtures containing relatively low concentrations of sucrose allow distinctions to be made between: 1) intakes stimulated by different access schedules and 2) opioid and dopaminergic modulation of those intakes. These results also suggest that brief bouts of food consumption involving fatty, sugar-rich foods may prove to be particularly resistant to pharmacological intervention.
Sustainable agriculture is considered the most viable means of meeting future food needs for the world's increasing population through its goal of delicately balancing crop productivity, ...profitability, natural resource utilization, sustainability of the soil–plant–water environment and environmental impacts. Precision agriculture is a proposed approach for achieving sustainable agriculture. Site-specific crop management (or site-specific management, SSM) refers to the application of precision agriculture to crop production. Site-specific crop management utilizes rapidly evolving information and electronic technologies to modify the management of soils, pests and crops in a site-specific manner as conditions within a field change spatially and temporarily. Geospatial measurements of apparent soil electrical conductivity (EC
a) are the most reliable and frequently used measurements to characterize within-field variability of edaphic properties for application to SSM. The collection of papers that comprises this special issue of
Computers and Electronics in Agriculture provides a review of the current technology and understanding of geospatial measurements of EC
a and current approaches for their application in SSM. The objective of this preface is to run a thread through the papers to show their interrelationship and to identify significant points. The spectrum of topics covered by the papers include: (i) a review of the use of EC
a measurements in agriculture, (ii) multi-dimensional EC
a modeling and inversion, (iii) theory and principles elucidating the edaphic properties that influence the EC
a measurement, (iv) EC
a survey protocols for characterizing spatial variability, (v) EC
a-directed response surface sampling design, (vi) designing and evaluating field-scale experiments using geospatial EC
a measurements, (vii) mapping of soil properties with EC
a, (viii) spatially characterizing EC
a and water content with time domain reflectometry (TDR), (ix) delineating productivity and SSM zones and (x) SSM methods for reclaiming salt-affected soils. The greatest potential for the application of geospatial measurements of EC
a in SSM is to provide reliable spatial information for directing soil sampling to identify and characterize the spatial variability of edaphic properties influencing crop yield. This in turn can be used to delineate SSM units, which are key components of SSM. The future of SSM depends upon the continued development and integration of information and electronic technologies that can identify and characterize, both temporally and spatially, not only edaphic properties but also topographical, biological, meteorological and anthropogenic factors influencing within-field variations in crop productivity. The implementation of global positioning system (GPS)-controlled variable-rate equipment will need spatial information to effectively determine input application rates. Because of their reliability, ease of measurement and flexibility, geospatial EC
a data will undoubtedly contribute a significant portion of the spatial soils-related information needed to direct variable-rate equipment.
Abstract Intermittent limited access to an optional source of dietary fat can induce binge-type behavior in rats. However, the ability of such access to alter the reinforcing efficacy of fat has not ...been clearly demonstrated. In this study, performance under progressive ratio one (PR1) and three (PR3) schedules of shortening (fat) reinforcement was assessed in non-food deprived rats ( n = 15/group). One group of rats had intermittent access to a dietary fat option (INT, 1-hour shortening access in the home cage each Monday, Wednesday, and Friday), whereas the other group had daily access to the fat option (D, 1-hour shortening access daily). Chow and water were continuously available. After five weeks, the INT group consumed more shortening during the 1-hour access period than did the D group. Rats were then trained to lever press for a solid shortening reinforcer (0.1 gm). INT rats earned significantly more reinforcers than did D rats under PR1, but not under PR3. Subgroups of INT and D rats ( n = 7 each) were matched on the amount of shortening consumed in the home cage during week five of the protocol and the PR data were reanalyzed. The INT subgroup earned significantly more reinforcers than the D subgroup did under PR1, but not PR3. These results demonstrate that: (1) intermittent access to shortening in the home cage, but not the amount consumed during the access period (i.e. bingeing), increases the reinforcing efficacy of solid shortening; and (2) the type of PR schedule is critical in delineating differences between the groups.
Twenty-four distinct outbreaks of probable chikungunya (CHIK) etiology were identified throughout Indonesia from September 2001 to March 2003, after a near 20-year hiatus of epidemic CHIK activity in ...the country. Thirteen outbreak reports were based on clinical observations alone, and 11 confirmed by serological/virological methods. Detailed epidemiological profiles of two investigated outbreaks in Bogor and Bekasi are presented. Human sera were screened using an ELISA for IgM and IgG anti-CHIK antibodies. Additionally, reverse transcriptase PCR and virus isolation were attempted for virus identification. The mean age of cases was 37 ± 18 years in Bogor and 33 ± 20 years in Bekasi. There was no outstanding case-clustering, although outbreak-affected households were observed to be geographically grouped within villages. The attack rates in Bogor and Bekasi were 2.8/1000 and 6.7/1000 inhabitants respectively. Both outbreaks started in the rainy season following increased
Aedes aegypti and
A. albopictus densities.
Abstract When non-food-deprived rats are given intermittent access to certain substances, consumption of those substances is greater than when more frequent access is provided. The present study ...examined the effects of three different shortening access conditions on subsequent shortening intake in rats. Each of the three different shortening conditions lasted five weeks and was followed by a five-week period in which shortening access was limited by time (1 h of availability) on either an Intermittent (Monday, Wednesday, Friday) or Daily schedule of access. In Part 1, limiting the quantity of shortening provided during the 1-h period of availability attenuated subsequent 1-h shortening intake in the Intermittent access group, but had no statistically significant effect in the Daily access group. In Part 2, unrestricted availability of shortening (24 h/day–7 days/week) attenuated subsequent 1-h shortening intake in all groups. In Part 3, shortening non-availability for five weeks enhanced subsequent 1-h shortening intake in all groups. It was also shown that rats under an Intermittent, but not a Daily, schedule of access consumed as much shortening during a 1-h period of availability, as was consumed in 24 h when shortening availability was unrestricted. These results demonstrate that while intermittent access is necessary and sufficient to stimulate binge-type eating in rats, the behavioral history can modulate binge size.
Soil salinity negatively impacts the productivity and profitability of western San Joaquin Valley (WSJV) farmland. Many factors, including drought, climate change, reduced water allocations, and ...land-use changes could worsen salinity conditions there, and in other agricultural lands in the state. Mapping soil salinity at regional and state levels is essential for identifying drivers and trends in agricultural soil salinity, and for developing mitigation strategies, but traditional soil sampling for salinity does not allow for accurate large-scale mapping. We tested remote-sensing modeling to map root zone soil salinity for farmland in the WSJV. According to our map, 0.78 million acres are salt affected (i.e., ECe greater than 4 dS/m), which represents 45% of the mapped farmland; 30% of that acreage is strongly or extremely saline. Independent validations of the remote-sensing estimations indicated acceptable to excellent correspondences, except in areas of low salinity and high soil heterogeneity. Remote sensing is a viable tool for helping landowners make decisions about land use and also for helping water districts and state agencies develop salinity mitigation strategies.
Broadband noise on supercontinuum spectra generated in microstructure fiber is shown to lead to amplitude fluctuations as large as 50% for certain input laser pulse parameters. We study this noise ...using both experimental measurements and numerical simulations with a generalized stochastic nonlinear Schrödinger equation, finding good quantitative agreement over a range of input-pulse energies and chirp values. This noise is shown to arise from nonlinear amplification of two quantum noise inputs: the input-pulse shot noise and the spontaneous Raman scattering down the fiber.
We have isolated a single tooth from a fiber laser-based optical frequency comb for nonlinear spectroscopy and thereby directly referenced the comb. An 89 MHz erbium fiber laser frequency comb is ...directly stabilized to the P(23) (1539.43 nm) overtone transition of (12)C(2)H(2) inside a hollow-core photonic crystal fiber. To do this, a single comb tooth is isolated and amplified from 20 nW to 40 mW with sufficient fidelity to perform saturated absorption spectroscopy. The fractional stability of the comb, ~7 nm away from the stabilized tooth, is shown to be 6 × 10(-12) at 100 ms gate time, which is over an order of magnitude better than that of a comb referenced to a GPS-disciplined Rb oscillator.
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