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PubMed1996

Projection of the lumbar pedicle and its morphometric analysis.

STUDY DESIGN: This study defined the projection point of the lumbar pedicle on its posterior aspect and its relation to a reliable landmark and reported pedicle dimensions based on 50 lumbar spines. OBJECTIVES: To establish the best starting point for a pedicle screw for passing the screw down the center (axis) of the pedicle; to describe quantitatively the relations of the pedicle projection point to a reliable landmark; and to evaluate the linear and angular dimensions of the lumbar pedicle. SUMMARY OF BACKGROUND DATA: Posterior transpedicular screw fixation has been most widely used for management of the unstable lumbar spine. Several studies of pedicular anatomy exist, but little quantitative data regarding the location of the lumbar pedicle axis for each level have been reported. METHODS: Fifty dry lumbar specimens (250 lumbar vertebrae) were obtained for study of the lumbar pedicle. Anatomic evaluation focused on determination of the projection point of the lumbar pedicle axis on the junction of the superior facet and the transverse process and measured the distance from the projection point to the midline of the transverse process for each level of the lumbar vertebrae. Pedicle dimensions, including linear and angular, also were measured. RESULTS: Differences in dimensions between men and women were not found to be statistically significant. The average distance from the projection point to the midline of the transverse process consistently changed from L1 to L5. Above L4, the projection point for men and women averaged 3.9 mm for L1, 2.8 mm for L2, and 1.4 mm for L3 superior to the midline of the transverse process, respectively. At L4, the projection point was close to the midline of the transverse process (0.5 mm inferior). At L5, the projection point was an average of 1.5 mm inferior to the midline of the transverse process. CONCLUSIONS: The average distance from the projection point of the lumbar pedicle axis to the midline of the transverse process consistently varied at different levels. This information may prove helpful in the placement of screws into the lumbar pedicle.

Adult↗
PubMed1997

The weighted-distance scheme: a globally optimizing projection ordering method for ART.

The order in which the projections are applied in the algebraic reconstruction technique (ART) has a great effect on speed of convergence, accuracy, and the amount of noise-like artifacts in the reconstructed image. In this paper, a new projection ordering scheme for ART is presented: the weighted-distance scheme (WDS). It heuristically optimizes the angular distance of a newly selected projection with respect to an extended sequence of previously applied projections. This sequence of influential projections may incorporate the complete set of all previously applied projections or any limited time interval subset thereof. The selection algorithm results in uniform sampling of the projection access space, minimizing correlation in the projection sequence. This produces more accurate images with less noise-like artifacts than previously suggested projection ordering schemes.

Algorithms↗
PubMedDate not supplied

A uniform projection method for motif discovery in DNA sequences.

Buhler and Tompa introduced the random projection algorithm for the motif discovery problem and demonstrated that this algorithm performs well on both simulated and biological samples. We describe a modification of the random projection algorithm, called the uniform projection algorithm, which utilizes a different choice of projections. We replace the random selection of projections by a greedy heuristic that approximately equalizes the coverage of the projections. We show that this change in selection of projections leads to improved performance on motif discovery problems. Furthermore, the uniform projection algorithm is directly applicable to other problems where the random projection algorithm has been used, including comparison of protein sequence databases.

Algorithms↗
PubMed1999

Content analysis and publication outcomes of projects by public health medicine registrars.

OBJECTIVE: To examine the content of the project work of public health medicine registrars in New Zealand and identify publication outcomes. METHOD: All projects submitted during 1987-97 were examined and key aspects captured on a database. Literature searches using Medline, Health Star, Index New Zealand and the NZ National Library catalogue were undertaken. RESULTS: A total of 355 registrar projects produced by 91 registrars were identified. Only 29% of these projects were associated with one or more publications that could be identified in electronic databases commonly available to New Zealanders and only 16% of them were associated with an article in the Medline-indexed literature. A possible cause for concern is the relatively small amount of project work (6% of projects) that was directly on Maori and/or Pacific Peoples' health. There also appears to be a relative lack of project work on chronic disease epidemiology and control, tobacco control and the socio-economic determinants of health. CONCLUSIONS: Given the relatively high quality of registrar project work, a publication rate of only 29% is probably suboptimal. The subject matter of registrar projects appears to infrequently address certain major areas of public health importance including Maori and Pacific Peoples' health. IMPLICATIONS: Consideration should be given to addressing these issues by those involved in public health medicine training.

Bibliometrics↗
PubMed1986

Young children's knowledge about visual perception: projective size and shape.

Although recent research indicates that an increased sensitivity to visual appearances develops around 4 or 5 years of age, evidence from perceptual studies suggests that certain types of appearances, that is, projective size and shape, are not noticed or understood until at least 7. 4 experiments investigated preschool children's knowledge of the projective size--distance and projective shape--orientation relationships. In Experiment 1, 3- and 4-year-olds were asked whether an object should be moved farther or nearer in order to increase or decrease its apparent size. 4-year-olds performed significantly better than chance, but 3-year-olds did not. Experiment 2 showed that 3-year-olds are able to perceive projective size changes, indicating that although they do not fully understand the projective size-distance relationship, the necessary perceptual information is potentially available to them. In Experiment 3, 3- and 4-year-olds were asked to indicate how a circular object should be rotated to make it appear either circular or elliptical. Again, 4-year-olds performed significantly better than chance, but 3-year-olds did not. Again also, the results of Experiment 4 indicate that although 3-year-olds are not aware of the projective shape-orientation relationship, they are capable of attending to changes in projective shape. Thus, the constraints on children's knowledge of the projective size-distance and projective shape-orientation relationships seem to be at least partly cognitive rather than wholly perceptual. These results are interpreted as further evidence for the acquisition of level 2 percept knowledge during early childhood.

Child Development↗
PubMed1975

Projections of pyramidal tract cells to alpha-motoneurones innervating hind-limb muscles in the monkey.

1. We have investigated the spatial organization of monosynaptic corticospinal projections to hind-limb motoneurones, using near threshold stimulation of the surface of the precentral gyrus to activate pyramidal tract (PT) cells and intracellular recording from motoneurones to detect the resulting e.p.s.p.s. 2. Monosynaptic e.p.s.p.s. of cortical origin were seen in all motoneurone species investigated, those of distal as well as of proximal hind-limb muscles. The proportion of motoneurones in which the e.s.p.s. were evoked and the amplitudes of the latter indicated a more extensive cortical projection to motor nuclei for distal than for proximal muscles, as previously found for forelimb motoneurones. 3. Cortical areas from which monosynaptic e.p.s.p.s. were evoked in individual motoneurones were remarkably large, most often between 3 and 7 mm2. Several motoneurones appeared to have two or three separate areas within the hind-limb division of the motor cortex. 4. Areas of location of pyramidal tract cells projecting to various motoneurones innervating one muscle were usually not identical. They overlapped often only partially or did not overlap at all. 5. Areas of location of pyramidal tract cells projecting to motor nuclei for different muscles often showed an extensive overlap. When it occurred, various motoneurones of a given motor nucleus had common cortical projection areas with motoneurones of other motor nuclei, either to synergistic or to antagonistic muscles. Our results give further evidence for overlapping of areas of cortical projections to motoneurones and speak against a mosaic-like organization of pyramidal tract cells projecting to different motor nuclei. 6. The rise times of cortically evoked e.p.s.p.s. indicate that the corticospinal tract fibres terminate on motoneurones at approximately similar distances from the soma as group Ia afferents. The small amplitudes of the majority of e.p.s.p.s. evoked by near threshold cortical stimulation therefore suggest that unitary e.p.s.p.s of cortical origin are small and that the density of pyramidal tract cells projecting to individual motoneurones is usually low, even in the centrum of projection areas. 7. Effects of intracortical stimulation depended on the stimulus strength. With currents of 2-3 muA, e.p.s.p.s were usually evoked in one motoneurone species or in close synergists. With currents of 5-10 muA, largest e.p.s.p.s a number of other motoneurones. Latencies of descending volleys in the lumbar corticospinal tract indicated that intracortical stimuli activated pyramidal tract cells indirectly; the effects of these stimuli could thus not be used to indicate the location of pyramidal tract cells responsible for them.

Animals↗
PubMed1978

The development of motor projection patterns in the chick hind limb.

1. Retrograde transport of horseradish peroxidase was used to map the initial projection patterns of lumbosacral motoneurones to the embryonic chick hind limb. 2. The stage 28 segmental projection pattern to each of the four primary muscle masses was characteristic and indistinguishable from the stage 36 projection pattern to the sum of the muscles derived from that mass. In addition, the adductor motoneurone pool was found to be similar in position (both rostro-caudal and mediolateral) at stages 29, 30, 32, 33 1/2 and 36. 3. Therefore axons from lumbosacral motoneurones project for the most part only to appropriate regions from early times shortly after they grow into the limb bud. Furthermore, the attainment of the segmental projection pattern occurs prior to the normal time of, and therefore without the aid of, cell death. This conclusion was supported by electrophysiological recordings made from muscle nerves. 4. A regionalization of the projection patterns within a single muscle mass could be shown both anatomically and physiologically prior to the cleavage of the mass into individual muscles and the projections were in a general way appropriate for the muscles derived from those regions. 5. Therefore the process of muscle cleavage does not in itself create the specific projection patterns observed, and motoneurone axons appear to grow to and to ramify and make synapses only within regions which correspond to their adult muscles. 6. Finally, the termination site of each motoneurone axon in the early limb was found to be tightly correlated in a somatotopic fashion with the position occupied by its soma in the cord. This suggests that some feature of the motoneurone related to its position may be of importance in achieving the specific projection patterns observed.

Action Potentials↗
PubMed1982

Electron microscopic observations of surface projections on Chlamydia psittaci reticulate bodies.

Electron microscopic observations were carried out to confirm the presence of surface projections on Chlamydia psittaci reticulate bodies (RBs). The morphology of the projections on RBs was identical with that on elementary bodies (EBs); one end of each projection was connected with the cytoplasmic membrane, but the other end of the projection protruded beyond the cell wall through a fine hole or rosette in the cell wall. The results demonstrated that the rosettes seen in RB cell walls were morphological markers indicating the presence of the surface projections. A statistical anaylsis of the number of projections on EBs and the number of rosettes in RB cell walls prepared at 10, 15, and 20 h after infection demonstrated that all RBs had the projections and that the number of projections was maximal by 10 h after infection and then decreased gradually to approximately the same number of projections on EBs.

Cell Membrane↗
PubMed2005

Characterization of pancreas-projecting rat dorsal motor nucleus of vagus neurons.

The electrophysiological and morphological properties of rat dorsal motor nucleus of the vagus (DMV) neurons innervating the pancreas were examined by using whole cell patch clamp recordings from brain stem slices and postfixation morphological reconstructions of Neurobiotin-filled neurons. Recordings were made from 178 DMV neurons whose projections had been identified by previous apposition of the fluorescent neuronal tracer DiI to the body of the pancreas. DMV neurons projecting to the pancreas had an input resistance of 434 +/- 14 M omega, an action potential duration of 3 +/- 0.1 ms, and an afterhyperpolarization of 18 +/- 0.4 mV amplitude and 108 +/- 7 ms time constant of decay; these electrophysiological properties resembled those of gastric-projecting neurons but were significantly different from those of intestinal-projecting neurons. Interestingly, 14 of 178 pancreas-projecting neurons showed the presence of a slowly developing afterhyperpolarization whose presence was not reported in DMV neurons projecting to any other gastrointestinal area. The morphological characteristics of pancreas-projecting neurons (soma area 274 +/- 12 microm2; soma diameter of 25 +/- 0.7 microm; soma form factor 0.74 +/- 0.01; segments 9.7 +/- 0.41), however, were similar to those of intestinal- but differed from those of gastric-projecting neurons. In summary, these results suggest that pancreas-projecting rat DMV neurons are heterogeneous with respect to some electrophysiological and morphological properties. These differences might underlie functional differences in the vagal modulation of pancreatic functions.

Animals↗
PubMed2002

Morphological characteristics and central projections of two types of interneurons in the visual pathway of Hermissenda.

The synaptic interactions between photoreceptors in the eye and second-order neurons in the optic ganglion of the nudibranch mollusk Hermissenda are well characterized. However, the higher-order neural circuitry of the visual system, consisting of cerebropleural interneurons that receive synaptic input from photoreceptors and project to pedal motor neurons that mediate visually guided behaviors, is only partially understood. In this report we have examined the central projections of two identified classes of cerebropleural interneurons that receive excitatory or inhibitory synaptic input from identified photoreceptors. The classification of the interneurons was based on both morphological and electrophysiological criteria. Type I interneurons received monosynaptic excitatory or inhibitory synaptic input from identified photoreceptors and projected to postsynaptic targets within the cerebropleural ganglion. Type II interneurons, characterized here for the first time, received polysynaptic excitatory or inhibitory synaptic input from identified photoreceptors and projected to postsynaptic targets in either the ipsilateral pedal ganglion or the contralateral cerebropleural ganglion. Type I interneurons exhibited unique intraganglionic projections to different regions of the cerebropleural ganglion, depending on whether they received excitatory or inhibitory synaptic input from identified photoreceptors. Type I interneurons that received monosynaptic excitatory input from identified B photoreceptors terminated near the cerebropleural commissure and had multiple regions of varicosities located at branches that projected from the primary axon. Type I interneurons that received monosynaptic inhibitory input from identified B photoreceptors projected to the anterior cerebropleural ganglion and exhibited varicosities localized to the terminal region of the primary axonal process. Type II interneurons that received polysynaptic inhibitory input from identified photoreceptors projected to the contralateral cerebropleural ganglion. Most type II interneurons that projected to the pedal ganglia received polysynaptic excitatory input from identified photoreceptors. These results indicate that there is at least one additional interneuron in the higher-order visual circuit between type I interneurons and pedal motor neurons responsible for the generation of phototactic locomotion in Hermissenda.

Action Potentials↗
PubMed2006

Identification of basolateral amygdala projection cells and interneurons using extracellular recordings.

This study tested whether firing rate and spike shape could be used to distinguish projection cells from interneurons in extracellular recordings of basolateral amygdala (BLA) neurons. To this end, we recorded BLA neurons in isoflurane-anesthetized animals with tungsten microelectrodes. Projection cells were identified by antidromic activation from cortical projection sites of the BLA. Although most projection cells fired spontaneously at low rates (<1 Hz), an important subset fired at higher rates (up to 6.8 Hz). In fact, the distribution of firing rates in projection cells and unidentified BLA neurons overlapped extensively, even though the latter cell group presumably contains a higher proportion of interneurons. The only difference between the two distributions was a small subset (5.1%) of unidentified neurons with unusually high firing rates (9-16 Hz). Similarly, distributions of spike durations in both cell groups were indistinguishable, although most of the fast-firing neurons had spike durations at the low end of the distribution. However, we observed that spike durations depended on the exact position of the electrode with respect to the recorded cell, varying by as much as 0.7 ms. Thus neither firing rate nor spike waveform allowed for unequivocal separation of projection cells from interneurons. Nevertheless, we propose the use of two firing rate cutoffs to obtain relatively pure samples of projection cells and interneurons: < or =1 Hz for projection cells and > or =7 Hz for fast-spiking interneurons. Supplemented with spike-duration cutoffs of > or =0.7 ms for projection cells and < or =0.5 ms for interneurons, this approach should keep instances of misclassifications to a minimum.

Action Potentials↗
PubMed1975

Somatotopic studies on red nucleus: spinal projection level and respective receptive fields.

The somatotopic inputs into red nucleus (RN) neurons have been studied with special reference to their level of projection in the spinal cord. As inputs we employed either volleys in predominantly cutaneous nerves of forelimb and hindlimb or cutaneous mechanoreceptor discharges evoked by taps to footpads of forelimb and hindlimb. There has been physiological confirmation of the anatomical findings that RD neurons projecting to the lumbar cord are located in the ventrolateral zone of the pars magnocellularis, whereas in the dorsomedial zone are RN neurons with cervical but not lumbar projection. Somatotopically there was found to be a differentiation of input to RN neurons according as they projected to the lumbar or only to the cervical cord. This finding was presented in the form both of tables and of somatotopic maps. As expected, this discrimination was more restrictive for the more selective inputs from pad taps than for nerve inputs. Nevertheless, forelimb inputs often had a considerable excitatory and inhibitory action on lumbar-projecting RN neurons, and vice versa for cervical-projecting neurons. There were two notable somatotopic findings that suggest specificities of connectivities. First, despite the large convergence of IP neurons onto RN neurons (about 50-fold), the degree of somatotopic discrimination was about the same for interpositus and RN neurons with two testing procedures: between inputs from forelimb and hindlimb; and between inputs from pads on one foot. Second, although there was in the interpositus nucleus a considerable topographical admixture of neurons with dominant forelimb or hindlimb inputs, the axonal projections of these neurons were apparently unscrambled on the way to the target RN neurons, so as to deliver the somatotopic specificities observed for two classes of RN neurons; those projecting down the spinal cord beyond L2 level, and those projecting to C2 but not L2. Finally, there is a general discussion of motor control with reference to the pathway; pars intermedia of anterior lobe of cerebellum leads to interpositus nucleus leads to red nucleus leads to rubrospinal tract leads to spinal motoneurons.

Animals↗
PubMed1996

Use of the sensitive anterograde tracer cholera toxin fragment B reveals new details of the central retinal projections in turtles.

Previous anterograde degeneration and autoradiographic studies have yielded inconsistent results on the extent and target areas of the central retinal projections in turtles. We used the highly sensitive anterograde and retrograde tracer, cholera toxin B fragment (CTB), to re-examine the central retinal projections in Pseudemys scripta elegans. In contrast to the results of the previous anterograde degeneration studies and autoradiographic studies, immunohistochemical detection of CTB-labeled central retinal axons and terminals revealed these projections with great morphological detail and clarity. In addition, the CTB labeling revealed much more extensive projections than previously realized to all known major retinorecipient areas, particularly in the dorsal and ventral lateral geniculate nuclei, the pretectal region, the nucleus of the basal optic root and the optic tectum. Although the contralateral projections were always much more extensive, ipsilateral projections were clearly present (and in some cases abundant) in all previously known retinorecipient areas. In addition, prominent contralateral (and lesser ipsilateral) retinal projections to several novel target, including the basal hypothalamus, the perirotundal nuclei, the suprapeduncular nucleus and the region between the pretectal nuclei and the tegmentum, were observed. Our results suggest that the use of CTB as a tracer to examine central retinal projections in diverse other species will show that central retinal projections are much more widespread and extensive than previously realized.

Animals↗
PubMed1984

Tangential organization of olfactory, association, and commissural projections to olfactory cortex in a species of reptile (Trionyx spiniferus), bird (Aix sponsa), and mammal (Tupaia glis).

Small amounts of tritiated leucine were injected into the olfactory bulb or anterior olfactory cortex of softshell turtles, wood ducks, and tree shrews in order to compare quantitatively the laminar distribution of olfactory bulb, association, and commissural projections to olfactory cortex. In all three species, a similar colaminar distribution of olfactory and association projections was found: the olfactory projections are restricted to the superficial cortical layer Ia, while the association projections are distributed into the deeper cortical layers Ib, II, and III. Differences among these three species were found in the origin and distribution of commissural projections. Whereas in tree shrews these fibers originate from third-order neurons and project into the deeper layers of the contralateral cortex (with the homolateral olfactory bulb projections), in softshell turtles and wood ducks, they originate from second-order neurons and project into the superficial layer of the contralateral cortex (with the homolateral olfactory bulb projections). These results, in conjunction with those obtained previously in other species, indicate that the basic tangential organization of mammalian olfactory cortex is retained, albeit with some modification, from a remote, reptilian ancestor.

Animals↗
PubMed1981

Principles of organization of a cerebro-cerebellar circuit. Micromapping the projections from cerebral (SI) to cerebellar (granule cell layer) tactile areas of rats.

We defined spatial patterns of organization of projections from somatosensory cerebral cortex (SI) to the somatosensory cerebellar cortex of anesthetized albino rats using microelectrode (stimulation and recording) micromapping methods and low-threshold cutaneous (tactile) stimulation. Two sampling strategies were used: (1) a single cerebral SI locus in layers V-VI was stimulated electrically, while a responding region of the cerebellar granule cell (GC) layer was systematically mapped with a recording electrode; (2) the SI stimulating electrode was used as the mapping electrode while the cerebellar GC electrode remain fixed. We found highly specific patterns of connections between somatotopically organized SI cortex and the somatotopically fractured tactile cerebellar cortex. Using threshold stimulating currents in SI, the projections from small populations of neural elements were found to be highly restricted, terminating within the confines of only those tactile cerebellar hemispheric locations having the same receptive fields (RFs). These SI-GC projections conform to the patchy mosaic pattern of organization previously shown for peripheral tactile projections. SI projections to GC patches were either contralateral or ipsilateral, depending on the laterality of the peripheral projections to that patch. Each SI focus projected to only a portion of a patch; projections from several adjacent SI loci overlapped serially within a patch. As with the peripherally evoked GC layer responses, SI-evoked GC responses were organized in a columnar fashion and were maximal at middle levels of the GC layer; SI-GC latencies were 5-8 ms. These data reveal that this tactile-related cerebro-cerebellar circuit exhibits precisely organized patterns of projection.

Animals↗
PubMed1989

Regeneration of the eighth cranial nerve. III. Central projections of the primary afferent fibers from individual vestibular receptors in the bullfrog.

The projection site in the central nervous system of individual end-organ branches of regenerated vestibular nerves was documented in bullfrogs. The eighth cranial nerve was surgically sectioned in 12 bullfrogs (Rana catesbeiana) and allowed to regenerate. Horseradish peroxidase was used to label the primary vestibular afferent fibers from the whole nerve (one frog) and the whole anterior branch (two frogs), and the individual receptor end-organ branches to the anterior semicircular canal (three frogs), the horizontal semicircular canal (three frogs), and the sacculus (three frogs). A sufficient number of fibers from the individual receptors were labeled in nine specimens to allow a description of their central projection pattern. The overall pattern of central projections of the regenerated nerves was similar to the pattern of normal nerves. In the eighth nerve root proper and in the area proximal to the vestibular nuclei, fibers from the anterior semicircular canal were ventral, fibers from the sacculus and posterior branch were dorsal, and fibers from the horizontal semicircular canal were in an intermediate position. In ventral, superior, and descending vestibular nuclei, a projection pattern was also identifiable in some specimens. The fibers of the anterior semicircular canal projected ventral to the fibers of the horizontal semicircular canal, with fibers from the posterior branch more dorsal. The saccular fibers projected to the dorsal aspect of the ventral nucleus and the ventral aspect of the dorsal nucleus. For the most part, projections in the regenerated specimens, as verified histologically, were comparable to individual end-organ projections previously identified in normal frogs. The only major discrepancy between the findings from the regenerated specimens and those from normal frogs was in the position of the vestibular tract and the innervation to the medial nucleus. The regenerated vestibular tract was shifted laterally in the brain stem. Regenerated thick and thin fibers were intermixed in the tract and projected to the medial nucleus. Normally, the thin fibers are lateral to the thick fibers in the tract. Therefore, the regenerated afferent fibers of the vestibular nerve selectively reinnervated the vestibular nuclei, and the fibers to the individual end-organs selectively reinnervated particular parts of the nuclei. In addition, the thick and thin regenerated fibers preserved the type of bouton endings normally found. The regenerated thick fibers had rare boutons en passant and a great number of collaterals, while the thin fibers had numerous boutons en passant and only a few collaterals.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2003

An evaluation of population projections by age.

A number of studies have evaluated the accuracy of projections of the size of the total population, but few have considered the accuracy of projections by age group. For many purposes, however, the relevant variable is the population of a particular age group, rather than the population as a whole. We investigated the precision and bias of a variety of age-group projections at the national and state levels in the United States and for counties in Florida. We also compared the accuracy of state and county projections that were derived from full-blown applications of the cohort-component method with the accuracy of projections that were derived from a simpler, less data-intensive version of the method. We found that age-group error patterns are different for national projections than for subnational projections; that errors are substantially larger for some age groups than for others; that differences in errors among age groups decline as the projection horizon becomes longer; and that differences in methodological complexity have no consistent impact on the precision and bias of age-group projections.

Adolescent↗
PubMed2001

Ecological approaches to rural development projects.

Most rural development projects include ecological considerations, and most conservation projects include some reference to sustainable development. However, conservation projects frequently fail because they do not incorporate local communities' perceptions and needs. Many development projects are also unsuccessful because they are not based on adequate ecological assessment. We focus here on the most important ecological issues to be addressed in order to place development projects in an ecosystem context. Such projects should incorporate updated and precise ecological concepts and methods. Some key ecological issues in development projects are the relationships between ecosystem functions, services, and sustainability, the concept of loose connectivity, the distinct and complementary concepts of ecosystem resistance and resilience, and the links between biodiversity and ecosystem functioning. We claim that an ecologically sound development project maximizes the preservation and improvement of ecosystem services, especially for local communities. We pose a series of questions aimed at placing rural development projects in an ecosystem context and suggest ways of organizing this information.

Ecology↗