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1.
Ecology ; 105(6): e4299, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38650359

ABSTRACT

Information on tropical Asian vertebrates has traditionally been sparse, particularly when it comes to cryptic species inhabiting the dense forests of the region. Vertebrate populations are declining globally due to land-use change and hunting, the latter frequently referred as "defaunation." This is especially true in tropical Asia where there is extensive land-use change and high human densities. Robust monitoring requires that large volumes of vertebrate population data be made available for use by the scientific and applied communities. Camera traps have emerged as an effective, non-invasive, widespread, and common approach to surveying vertebrates in their natural habitats. However, camera-derived datasets remain scattered across a wide array of sources, including published scientific literature, gray literature, and unpublished works, making it challenging for researchers to harness the full potential of cameras for ecology, conservation, and management. In response, we collated and standardized observations from 239 camera trap studies conducted in tropical Asia. There were 278,260 independent records of 371 distinct species, comprising 232 mammals, 132 birds, and seven reptiles. The total trapping effort accumulated in this data paper consisted of 876,606 trap nights, distributed among Indonesia, Singapore, Malaysia, Bhutan, Thailand, Myanmar, Cambodia, Laos, Vietnam, Nepal, and far eastern India. The relatively standardized deployment methods in the region provide a consistent, reliable, and rich count data set relative to other large-scale pressence-only data sets, such as the Global Biodiversity Information Facility (GBIF) or citizen science repositories (e.g., iNaturalist), and is thus most similar to eBird. To facilitate the use of these data, we also provide mammalian species trait information and 13 environmental covariates calculated at three spatial scales around the camera survey centroids (within 10-, 20-, and 30-km buffers). We will update the dataset to include broader coverage of temperate Asia and add newer surveys and covariates as they become available. This dataset unlocks immense opportunities for single-species ecological or conservation studies as well as applied ecology, community ecology, and macroecology investigations. The data are fully available to the public for utilization and research. Please cite this data paper when utilizing the data.


Subject(s)
Forests , Tropical Climate , Vertebrates , Animals , Vertebrates/physiology , Photography/methods , Asia , Biodiversity
2.
Am J Ophthalmol Case Rep ; 21: 101019, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33553806

ABSTRACT

PURPOSE: To describe the clinical course and microbial properties of the first two reported cases of nutritionally variant Streptococci (Granulicatella adiacens and Abiotrophia defectiva) endophthalmitis following intravitreal anti-vascular endothelial growth factor injection (IVI). OBSERVATIONS: A 74 year-old female developed Granulicatella adiacens endophthalmitis following IVI. The patient underwent a pars plana vitrectomy and visual acuity recovered to 20/30 in six weeks. Similarly, an 88 year-old male developed Abiotrophia defectiva endophthalmitis after IVI. After a pars plana vitrectomy, the visual acuity recovered to 20/60 at five weeks. CONCLUSIONS AND IMPORTANCE: Endophthalmitis due to Streptococcus species has traditionally resulted in uniformly poor visual outcomes. However, nutritionally variant Streptococci, now reclassified as Granulicatella and Abiotrophia species, appear to have a less aggressive clinical course and better visual acuity outcomes. To the authors' knowledge, these are the first reports of nutritionally variant Streptococci following IVI related endophthalmitis.

3.
Integr Zool ; 16(1): 19-32, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32627329

ABSTRACT

Resource depletion exerts opposing pressures on co-occurring consumers to expand diets while limiting overlap with competitors. Using foraging theory as a framework, we tested the effects of prey availability on diet specialization and overlap among competing Asian predators: dhole, leopard, and tiger. We used scat analysis from a prey-poor site, combined with a quantitative synthesis of 40 other diet studies, to determine biomass of different prey types consumed by each predator. We then assessed diet composition in relation to prey density, and compared diet breadth and overlap between prey-poor and prey-rich sites. In prey rich areas, all three predators specialized on energetically profitable medium and large ungulates (>30 kg), resulting in narrow, overlapping niches. Each predator shifted toward less profitable small-bodied prey (≤30 kg) as preferred ungulates declined, whereas consumption of preferred ungulates was unrelated to small prey abundance, as predicted by foraging theory. Diet breadths doubled under prey depletion (except leopard), but overlap declined as diets diverged via species-specific traits that facilitated capture of different types of alternative prey. Asia's apex predators adapt similarly to depletion of mutually preferred ungulates by switching to more numerous but less profitable small prey. Yet they can also partition a depleted prey base through intrinsic niche differences, thereby avoiding competitive exclusion. Our findings illuminate the stabilizing properties of adaptive foraging and niche differences in ecological communities, and provide insights into the behavior and resilience of Asia's endangered apex predators in response to prey depletion in the heavily poached forests of this region.


Subject(s)
Appetitive Behavior , Carnivora/physiology , Diet , Predatory Behavior , Animals , Asia, Southeastern , Feces , Sympatry , Thailand
4.
PLoS One ; 13(11): e0207114, 2018.
Article in English | MEDLINE | ID: mdl-30408090

ABSTRACT

With less than 3200 wild tigers in 2010, the heads of 13 tiger-range countries committed to doubling the global population of wild tigers by 2022. This goal represents the highest level of ambition and commitment required to turn the tide for tigers in the wild. Yet, ensuring efficient and targeted implementation of conservation actions alongside systematic monitoring of progress towards this goal requires that we set site-specific recovery targets and timelines that are ecologically realistic. In this study, we assess the recovery potential of 18 sites identified under WWF's Tigers Alive Initiative. We delineated recovery systems comprising a source, recovery site, and support region, which need to be managed synergistically to meet these targets. By using the best available data on tiger and prey numbers, and adapting existing species recovery frameworks, we show that these sites, which currently support 165 (118-277) tigers, have the potential to harbour 585 (454-739) individuals. This would constitute a 15% increase in the global population and represent over a three-fold increase within these specific sites, on an average. However, it may not be realistic to achieve this target by 2022, since tiger recovery in 15 of these 18 sites is contingent on the initial recovery of prey populations, which is a slow process. We conclude that while sustained conservation efforts can yield significant recoveries, it is critical that we commit our resources to achieving the biologically realistic targets for these sites even if the timelines are extended.


Subject(s)
Endangered Species , Tigers , Animals , Asia , Goals , Population Density , Predatory Behavior , Time Factors
5.
J Neuroophthalmol ; 38(3): 285-291, 2018 09.
Article in English | MEDLINE | ID: mdl-28885451

ABSTRACT

BACKGROUND: Vision-based measures have been shown to be useful markers in multiple sclerosis (MS), Alzheimer and Parkinson disease. Therefore, these testing paradigms may have applications to populations explaining repetitive head trauma that has been associated with long-term neurodegenerative sequelae. We investigated retinal structure and visual function in professional collision sport athletes compared to age- and race-matched control participants. METHODS: In this cross-sectional study, participants underwent spectral-domain optical coherence tomography (OCT) measurements of peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC = ganglion cell + inner plexiform layers) thickness. High-contrast visual acuity (100% level), low-contrast letter acuity (LCLA) (1.25% and 2.5% levels), and King-Devick Test of rapid number naming performance were administered. Vision-specific quality of life (QOL) measures were assessed. RESULTS: Among 46 collision sport athletes (boxing, n = 14; football, n = 29; ice hockey, n = 3) and 104 control participants, average RNFL thickness was a significant predictor of athlete vs control status with athletes demonstrating 4.8-µm of thinning compared to controls (P = 0.01, generalized estimating equation [GEE] models accounting for age and within-subject, intereye correlations). Athlete vs control status was not a predictor of RNFL thickness for the subgroup of football players in this cohort (P = 0.60). Binocular (P = 0.001) and monocular (P = 0.02) LCLA at 2.5% contrast and vision-specific QOL (P = 0.04) were significant predictors of athlete vs control status (GEE models accounting for age and within-subject, intereye correlations). Rapid number naming performance times were not significantly different between the control and athlete groups. CONCLUSIONS: This study showed that retinal axonal and neuronal loss is present among collision sport athletes, with most notable differences seen in boxers. These findings are accompanied by reductions in visual function and QOL, similar to patterns observed in multiple sclerosis, Alzheimer and Parkinson diseases. Vision-based changes associated with head trauma exposure that have the potential to be detected in vivo represent a unique opportunity for further study to determine if these changes in collision sport athletes are predictive of future neurodegeneration.


Subject(s)
Athletes , Athletic Injuries/complications , Brain Concussion/complications , Retinal Diseases/diagnosis , Retinal Ganglion Cells/pathology , Tomography, Optical Coherence/methods , Visual Acuity , Adult , Athletic Injuries/diagnosis , Brain Concussion/diagnosis , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Retinal Diseases/etiology
6.
Conserv Biol ; 31(6): 1257-1270, 2017 12.
Article in English | MEDLINE | ID: mdl-29030915

ABSTRACT

Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.


Subject(s)
Conservation of Natural Resources/legislation & jurisprudence , Forestry/legislation & jurisprudence , Forests , Politics , Biodiversity , Myanmar
7.
Integr Zool ; 7(4): 389-399, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23253370

ABSTRACT

Southeast Asia's tropical forests suffer the highest rates of deforestation and disturbance of any on Earth, with poorly understood impacts on native fauna. Asian tapirs (Tapirus indicus) are among the least studied of the large mammals in these forests. Using records from 9 camera trap surveys in 7 of the largest (>1000 km(2) ) protected area complexes, we assessed the influence of environmental variation and human-induced disturbance on tapir occurrence. Tapirs were detected at 13% of locations sampled, significantly associated with evergreen forest (P < 0.001). A multiple logistic regression model predicted tapir presence 87% of the time. According to this model, tapir occurrence was positively influenced by annual rainfall and proximity to the forest edge. However, tapirs may not avoid edges but instead prefer wetter evergreen forest, a habitat type that tended to occur further from the forest edge at higher elevations in our particular study sites (P < 0.001). By comparison, 4 other wild ungulate species that share habitats with tapirs showed a range of differing responses. Tapirs are expected to be less sensitive to disturbance because they are not targets for hunting and trade, and are almost entirely active at night, so avoid peak traffic periods in parks. Tapir populations in Thailand may be more stable than in other parts of their global range because rates of forest loss have decreased >40% over the past 20 years. We recommend surveys to fill gaps in the understanding of the status in lesser-known protected areas, research to better understand the fine-scale environmental influences on behavior and habitats of tapirs, and other forest ungulates, and continued legal status for tapirs in the highest category of protection.


Subject(s)
Adaptation, Physiological/physiology , Conservation of Natural Resources/methods , Ecosystem , Environment , Perissodactyla/physiology , Trees , Animals , Human Activities , Logistic Models , Photography , Rain , Species Specificity , Thailand
9.
PLoS One ; 6(1): e14509, 2011 Jan 20.
Article in English | MEDLINE | ID: mdl-21283792

ABSTRACT

BACKGROUND: Ecologically similar species often coexist by partitioning use of habitats or resources. Such partitioning can occur through divergent or shared niches. We investigated overlap in habitat use and spatial co-occurrence by sympatric Asiatic black bears and sun bears in three habitats in Thailand, and thereby assessed which niche model best accounts for their coexistence. METHODS/PRINCIPAL FINDINGS: We used density of species-specific signs to assess habitat use. Signs of both bear species occurred in all three habitats, and on >60% of sampling transects. Both species fed mostly on fruit; insect feeding signs were uncommon, and were mostly from sun bears. Significant differences in habitat use occurred only in montane forest, the habitat in which fruit was most abundant; incidence of black bear sign there was six times higher than that of sun bears. Habitat use was similar between the two species in the other habitats, which comprised 85% of the area. Of 10 habitat attributes examined, fruiting tree density was the best predictor of occurrence for both species. Models that included interspecific competition (fresh foraging activity of the other species) were less supported than the top models without competition. CONCLUSIONS/SIGNIFICANCE: Bear species co-occurrence at both coarse and fine spatial scales and use of the same resources (fruit trees) indicated common niche preferences. However, their habitat use differed in ways expected from their physical differences: larger black bears dominated in the most fruit-rich habitat, and smaller sun bears used less-preferred insects. These results indicate broadly overlapping fundamental niches combined with asymmetric competition-features consistent with the concept of shared preference niches. This model of the niche has received little attention in ecology, but appears to be relatively common in nature.


Subject(s)
Ecosystem , Food Preferences/physiology , Trees , Ursidae/physiology , Animals , Feeding Behavior , Thailand , Tropical Climate
10.
Conserv Biol ; 20(5): 1391-401, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17002757

ABSTRACT

Depressed mammal densities characterize the interior of many Southeast Asian protected areas, and are the result of commercial and subsistence hunting. Local people are part of this problem but can participate in solutions through improved partnerships that incorporate local knowledge into problem diagnosis. The process of involving local people helps build a constituency that is more aware of its role (positive and negative) in a protected area and generates site-specific conservation assessments for management planning. We illustrate the practical details of initiating such a partnership through our work in a Thai wildlife sanctuary. Many protected areas in Southeast Asia present similar opportunities. In local workshops, village woodsmen were led through ranking exercises to develop a spatially explicit picture of 20-year trends in the abundance of 31 mammal species and to compare species-specific causes for declines. Within five taxonomic groups, leaf monkeys (primates), porcupines (rodents), tigers (large carnivores), civets (small carnivores), and elephants (ungulates) had declined most severely (37-74%). Commercial hunting contributed heavily to extensive population declines for most species, and subsistence hunting was locally significant for some small carnivores, leaf monkeys, and deer. Workshops thus clarified which species were at highest risk of local extinction, where the most threatened populations were, and causes for these patterns. Most important, they advanced a shared problem definition, thereby unlocking opportunities for collaboration. As a result, local people and sanctuary managers have increased communication, initiated joint monitoring and patrolling, and established wildlife recovery zones. Using local knowledge has limitations, but the process of engaging local people promotes collaborative action that large mammals in Southeast Asia need.


Subject(s)
Conservation of Natural Resources/methods , Ecosystem , Mammals , Animals , Animals, Wild , Community Participation , Conservation of Natural Resources/legislation & jurisprudence , Data Collection , Education , Thailand
12.
Arch Ophthalmol ; 122(12): 1801-7, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15596583

ABSTRACT

BACKGROUND: Diffuse macular edema (DME) and/or aberrant neovascularization (NV) can cause vision loss in diabetic retinopathy (DR) and may be modulated by growth factors and chemokines. The chemokine stromal-derived factor 1 (SDF-1) is a potent stimulator of vascular endothelial growth factor (VEGF) expression, the main effector of NV, and the key inducer of vascular permeability associated with DME. Circulating endothelial cell precursors migrating in response to SDF-1 participate in NV. OBJECTIVE: To investigate the relationship between SDF-1 and (VEGF) in vitreous of patients with varying degrees of DR and DME before and after intraocular injection of triamcinolone acetonide, used to treat refractory DME. METHODS: In this prospective study, 36 patients were included and observed for 6 months. Vitreous VEGF and SDF-1 levels were measured by enzyme-linked immunosorbent assay in samples obtained immediately before and 1 month after injection of triamcinolone. RESULTS: Both VEGF and SDF-1 were significantly higher (P<.01) in patients with proliferative DR than in patients with nonproliferative DR. Levels of SDF-1 were markedly increased in patients with DME compared with those without DME. Vascular endothelial growth factor correlated with SDF-1 levels and disease severity (r(2) = 0.88). CONCLUSIONS: Triamcinolone administration resulted in dramatic reductions of VEGF and SDF-1 to nearly undetectable levels, eliminated DME, and caused regression of active NV. Our results support a role for SDF-1 and VEGF in the pathogenesis of the adverse visual consequences of DR and suggest that the elimination of DME with regression and/or initiation of fibrosis of NV after triamcinolone injection may be due to the suppression of VEGF and SDF-1.


Subject(s)
Chemokines, CXC/metabolism , Diabetic Retinopathy/metabolism , Glucocorticoids/administration & dosage , Macular Edema/metabolism , Triamcinolone Acetonide/administration & dosage , Vascular Endothelial Growth Factor A/metabolism , Vitreous Body/metabolism , Aged , Blood-Retinal Barrier , Capillary Permeability , Cells, Cultured , Chemokine CXCL12 , Chemotaxis/physiology , Diabetic Retinopathy/drug therapy , Endothelium, Vascular/physiology , Enzyme-Linked Immunosorbent Assay , Female , Fluorescein Angiography , Humans , Injections , Macular Edema/drug therapy , Male , Middle Aged , Prospective Studies , Tomography, Optical Coherence
13.
Retina ; 24(4): 556-9, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15300076

ABSTRACT

PURPOSE: To report a large series of eyes in which there was a posterior dislocation of a posterior chamber intraocular lens (PCIOL). During vitrectomy, the dislocated intraocular lens (IOL) was removed through an enlarged pars plana sclerotomy. An anterior chamber IOL (ACIOL) was implanted primarily or secondarily. METHODS: We conducted a retrospective chart review of 59 eyes of 58 patients with posterior dislocation of a PCIOL. RESULTS: Fifty-four eyes (92%) had improved visual acuity after surgery. Sixty-six percent (39 of 59) of eyes achieved at least 20/40 vision; 25% (15 of 59) of eyes achieved a visual acuity of 20/50 to 20/200; and 8% (5 of 59) of eyes achieved less than 20/200 vision. In 32 (54%) eyes, PCIOL removal was combined with primary implantation of an ACIOL. In 27 (46%) eyes, the PCIOL was removed and the referring ophthalmologist placed a secondary ACIOL. Intraoperative complications consisted of limited suprachoroidal hemorrhage in 2 (3%) eyes. Postoperative complications consisted of retinal detachment in 5 (8%) eyes, cystoid macular edema in 13 (22%) eyes, and vitreous hemorrhage in 3 (5%) eyes. CONCLUSION: Posterior dislocation of a PCIOL may be managed safely by removal of the dislocated PCIOL through the pars plana.


Subject(s)
Device Removal , Foreign-Body Migration/surgery , Lenses, Intraocular , Vitrectomy/methods , Aged , Aged, 80 and over , Anterior Chamber/surgery , Female , Foreign-Body Migration/etiology , Humans , Intraoperative Complications , Lens Implantation, Intraocular , Male , Middle Aged , Postoperative Complications , Retrospective Studies , Sclerostomy , Visual Acuity
14.
Ophthalmology ; 109(12): 2303-7, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12466174

ABSTRACT

OBJECTIVE: To examine the visual and anatomic results of bimanual vitrectomy surgery with the multiport illumination system (MIS) in eyes with advanced diabetic traction retinal detachment. DESIGN: Retrospective, noncomparative interventional case series. PARTICIPANTS: Sixty-seven consecutive eyes in 62 patients having vitrectomy with the MIS. METHODS: During surgery, the vitreous, the posterior hyaloid membrane, and fibrovascular proliferative tissue were removed by using bimanual dissection made possible by the MIS. MAIN OUTCOME MEASURES: Retinal reattachment rate, visual function, and postoperative complications were compared with previously published series of vitrectomy for diabetic traction retinal detachment. RESULTS: With a minimum of 6 months of follow-up, complete retinal reattachment was achieved in 62 eyes (93%), and macular attachment was achieved in all 67 eyes. Vision was stabilized or improved in 51 eyes (72%), and 5/200 vision was achieved in 47 eyes (70%). No unique complications, such as incision-related retinal tears, occurred. CONCLUSION: MIS allows bimanual surgery during vitrectomy for diabetic traction retinal detachment, with good visual and anatomic results.


Subject(s)
Diabetic Retinopathy/surgery , Lighting/methods , Retinal Detachment/surgery , Vitrectomy/methods , Adult , Aged , Diabetic Retinopathy/complications , Female , Humans , Lighting/instrumentation , Male , Middle Aged , Postoperative Complications , Retinal Detachment/etiology , Retrospective Studies , Visual Acuity , Vitrectomy/instrumentation
15.
Retina ; 22(1): 48-52, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11884878

ABSTRACT

PURPOSE: To report results applying diode laser photocoagulation to both the peripheral avascular retina and the ridge in stage 3+ threshold retinopathy of prematurity. METHODS: The authors performed a retrospective review of 82 consecutive eyes in 43 preterm infants with threshold disease who had both the peripheral avascular retina and the ridge treated with diode laser photocoagulation. With a minimum follow-up of 3 months, these eyes were evaluated for intraoperative and postoperative complications and long-term anatomic results. RESULTS: A favorable anatomic outcome occurred in 79 eyes (96%). There were no intraoperative complications. Postoperative intraocular hemorrhage occurred in eight eyes (10%) and resolved without sequelae. Supplemental laser was required in only two eyes (2%). CONCLUSIONS: Diode laser photocoagulation to the ridge and peripheral avascular retina in threshold retinopathy of prematurity is associated with a favorable anatomic outcome. The risk of postoperative intraocular hemorrhage and the need for supplemental laser photocoagulation is low.


Subject(s)
Laser Coagulation , Retina/surgery , Retinal Vessels/surgery , Retinopathy of Prematurity/surgery , Follow-Up Studies , Gestational Age , Humans , Infant , Infant, Newborn , Intraoperative Complications , Postoperative Complications , Retinopathy of Prematurity/classification , Retrospective Studies , Treatment Outcome
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