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2.
Proc Natl Acad Sci U S A ; 120(23): e2208376120, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37252987

RESUMEN

Demand for food products, often from international trade, has brought agricultural land use into direct competition with biodiversity. Where these potential conflicts occur and which consumers are responsible is poorly understood. By combining conservation priority (CP) maps with agricultural trade data, we estimate current potential conservation risk hotspots driven by 197 countries across 48 agricultural products. Globally, a third of agricultural production occurs in sites of high CP (CP > 0.75, max = 1.0). While cattle, maize, rice, and soybean pose the greatest threat to very high-CP sites, other low-conservation risk products (e.g., sugar beet, pearl millet, and sunflower) currently are less likely to be grown in sites of agriculture-conservation conflict. Our analysis suggests that a commodity can cause dissimilar conservation threats in different production regions. Accordingly, some of the conservation risks posed by different countries depend on their demand and sourcing patterns of agricultural commodities. Our spatial analyses identify potential hotspots of competition between agriculture and high-conservation value sites (i.e., 0.5° resolution, or ~367 to 3,077km2, grid cells containing both agriculture and high-biodiversity priority habitat), thereby providing additional information that could help prioritize conservation activities and safeguard biodiversity in individual countries and globally. A web-based GIS tool at https://agriculture.spatialfootprint.com/biodiversity/ systematically visualizes the results of our analyses.


Asunto(s)
Comercio , Conservación de los Recursos Naturales , Animales , Bovinos , Conservación de los Recursos Naturales/métodos , Internacionalidad , Ecosistema , Biodiversidad , Agricultura/métodos
3.
Ecol Evol ; 12(5): e8884, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35600699

RESUMEN

Environmental heterogeneity is one of the most influential factors that create compositional variation among local communities. Greater compositional variation is expected when an environmental gradient encompasses the most severe conditions where species sorting is more likely to operate. However, evidence for stronger species sorting at severer environment has typically been obtained for less mobile organisms and tests are scarce for those with higher dispersal ability that allows individuals to sensitively respond to environmental stress. Here, with the dynamics of fish communities in a Japanese bay revealed by environmental DNA metabarcoding analyses as a model case, we tested the hypothesis that larger environmental heterogeneity caused by severe seasonal hypoxia (lower concentration of oxygen in bottom waters in summer) leads to larger variation of species composition among communities. During summer, fish species richness was lower in the bottom layer, suggesting the severity of the hypoxic bottom water. In contrast to the prediction, we found that although the environmental parameters of bottom and surface water was clearly distinct in summer, fish species composition was more similar between the two layers. Our null model analysis suggested that the higher compositional similarity during hypoxia season was not a result of the sampling effect reflecting differences in the alpha or gamma diversity. Furthermore, a shift in the species occurrence from bottom to surface layers was observed during hypoxia season, which was consistent across species, suggesting that the severe condition in the bottom adversely affected fish species irrespective of their identity. These results suggest that larger environmental heterogeneity does not necessarily lead to higher compositional variation once the environmental gradient encompasses extremely severe conditions. This is most likely because individual organisms actively avoided the severity quasi-neutrally, which induced mass effect-like dispersal and lead to the mixing of species composition across habitats. By showing counter evidence against the prevailing view, we provide novel insights into how species sorting by environment acts in heterogeneous and severe conditions.

4.
Sci Rep ; 11(1): 11938, 2021 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34099758

RESUMEN

Nonlinear phenomena are universal in ecology. However, their inference and prediction are generally difficult because of autocorrelation and outliers. A traditional least squares method for parameter estimation is capable of improving short-term prediction by estimating autocorrelation, whereas it has weakness to outliers and consequently worse long-term prediction. In contrast, a traditional robust regression approach, such as the least absolute deviations method, alleviates the influence of outliers and has potentially better long-term prediction, whereas it makes accurately estimating autocorrelation difficult and possibly leads to worse short-term prediction. We propose a new robust regression approach that estimates autocorrelation accurately and reduces the influence of outliers. We then compare the new method with the conventional least squares and least absolute deviations methods by using simulated data and real ecological data. Simulations and analysis of real data demonstrate that the new method generally has better long-term and short-term prediction ability for nonlinear estimation problems using spawner-recruitment data. The new method provides nearly unbiased autocorrelation even for highly contaminated simulated data with extreme outliers, whereas other methods fail to estimate autocorrelation accurately.

5.
BMC Ecol ; 17(1): 37, 2017 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-29228938

RESUMEN

BACKGROUND: Invasive ecosystem engineers can facilitate their invasions by modifying the physical environment to improve their own performance, but this positive feedback process has rarely been tested empirically except in sessile organisms. The invasive crayfish Procambarus clarkii is an ecosystem engineer that destroys aquatic macrophytes, which provide a physical refuge for animal prey, and this destruction is likely to enhance vulnerability to predators. Using two series of mesocosm experiments, we tested the hypothesis that the invasive crayfish increases its feeding efficiency on animal prey by reducing submerged macrophytes, thus increasing its individual growth rate in a positive density-dependent manner. RESULTS: In the first experiment, increasing crayfish density reduced both macrophytes and animal prey (dragonfly and chironomid larvae) and, importantly, increased the growth rate of individual crayfish, in accordance with our expectation. In the second experiment, we used artificial macrophytes to clarify whether the physical architecture of macrophytes itself protects animal prey and limits crayfish growth rate. Increasing the artificial macrophyte quantity not only increased the survival of animal prey, but also retarded the crayfish growth rate. CONCLUSIONS: We conclude that macrophytes strengthen bottom-up control of crayfish, but this effect can be relaxed by increasing the density of crayfish via reduction in macrophytes. This positive feedback process may explain the crayfish outbreaks and regime shifts occasionally observed in invaded freshwater ecosystems.


Asunto(s)
Astacoidea/fisiología , Ecosistema , Cadena Alimentaria , Especies Introducidas , Animales , Astacoidea/crecimiento & desarrollo , Chironomidae/crecimiento & desarrollo , Conducta Alimentaria , Agua Dulce , Larva/crecimiento & desarrollo , Odonata/crecimiento & desarrollo , Desarrollo de la Planta , Densidad de Población
6.
Gynecol Endocrinol ; 31(8): 643-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26291801

RESUMEN

To evaluate the outcomes of patients treated with cyclic administration of dienogest after ovarian endometriotic cystectomy, following the completion of treatment. We retrospectively evaluated 26 patients treated with dienogest (2 mg/day) after cystectomy (revised American Society for Reproductive Medicine [r-ASRM] stage III-IV) in a pilot study. Dienogest was administered cyclically, for a total of six cycles, each comprising three weeks on and one week off. Outcomes of interest included severity of menstrual pain and recurrence of cysts at baseline, during the immediate post-treatment period and at the final outpatient follow-up. The mean outpatient follow-up period was 45.0 months. The visual analog scale score for menstrual pain following 6 cycles of dienogest treatment was significantly lower than that at baseline; it remained low at the final follow-up. The recurrence rates of cysts were 4% and 21% at 24 and 48 months after the completion of dienogest treatment, respectively. Six patients with recurrent disease were all classified as having r-ASRM stage IV. Our results suggest that cyclic dienogest for six months after cystectomy could relieve menstrual pain and reduce the recurrence of cysts, for approximately four years. The necessary treatment period for patients with r-ASRM stage IV disease requires further study.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Nandrolona/análogos & derivados , Quistes Ováricos/cirugía , Dolor Pélvico/prevención & control , Adulto , Antineoplásicos Hormonales/administración & dosificación , Esquema de Medicación , Femenino , Humanos , Laparoscopía , Nandrolona/administración & dosificación , Nandrolona/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
7.
Am Nat ; 183(5): 625-37, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24739195

RESUMEN

Declines of apex predators can cause dramatic increases of smaller predators and ensuing collapses of their prey. However, recent empirical evidence finds that the disappearance of apex predators does not reduce but can increase prey populations. This poses a great challenge in managing species interactions involving mesopredator release. Here we analyze a mathematical model to explain variable consequences of apex predator loss and to develop management guidelines for prey conservation. The model formulates an intraguild predation system (apex predators, mesopredators, and their shared prey) with mesopredators supplied with additional alternative prey. We show that apex predator loss causes only negative effects on shared prey without alternative prey but has either negative or positive effects with alternative prey. Moreover, when alternative prey is highly abundant, apex predator loss causes strong mesopredator release and reduces shared prey greatly. Finally, the model suggests that a viable management strategy to restore shared prey under much uncertainty about a target system is to allocate a limited control effort not only to both predators but also to alternative prey. Alternative prey for mesopredators may be a crucial ingredient that controls the cascading dynamics of intraguild predation systems and should be considered as an important management target.


Asunto(s)
Cadena Alimentaria , Dinámica Poblacional , Conducta Predatoria/fisiología , Animales , Conducta Apetitiva , Especies Introducidas , Modelos Teóricos
8.
Ecol Evol ; 3(14): 4711-21, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24363899

RESUMEN

For maintaining social and financial support for eradication programs of invasive species, quantitative assessment of recovery of native species or ecosystems is important because it provides a measurable parameter of success. However, setting a concrete goal for recovery is often difficult owing to lack of information prior to the introduction of invaders. Here, we present a novel approach to evaluate the achievement level of invasive predator management based on the carrying capacity of endangered species estimated using long-term monitoring data. In Amami-Oshima Island, Japan, where the eradication project of introduced small Indian mongoose is ongoing since 2000, we surveyed the population densities of four endangered species threatened by the mongoose (Amami rabbit, the Otton frog, Amami tip-nosed frog, and Amami Ishikawa's frog) at four time points ranging from 2003 to 2011. We estimated the carrying capacities of these species using the logistic growth model combined with the effects of mongoose predation and environmental heterogeneity. All species showed clear tendencies toward increasing their density in line with decreased mongoose density, and they exhibited density-dependent population growth. The estimated carrying capacities of three endangered species had small confidence intervals enough to measure recovery levels by the mongoose management. The population density of each endangered species has recovered to the level of the carrying capacity at about 20-40% of all sites, whereas no individuals were observed at more than 25% of all sites. We propose that the present approach involving appropriate monitoring data of native organism populations will be widely applicable to various eradication projects and provide unambiguous goals for management of invasive species.

9.
Gynecol Oncol ; 131(3): 674-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24060414

RESUMEN

OBJECTIVE: Taste disturbance is known to occur as one of the adverse events associated with chemotherapy for gynecological cancer, but few studies have attempted to assess it in practical terms. Therefore, a range of taste tests was performed in gynecological cancer patients. METHODS: The patients were 23 women with gynecological cancer being treated with anticancer agents. Subjective symptoms of altered taste were classified, and objective findings were obtained with the following four gustatory tests: serum trace element (zinc, copper, iron) levels, tongue cultures, electrogustometry, and the filter paper disc tests. RESULTS: Of the 23 subjects, 11 perceived taste disturbances. The serum zinc level was consistently below the lower limit of normal. On tongue cultures, indigenous bacteria were seen in all patients during the entire treatment period. Electrogustometry revealed a tendency for the development of hypogeusia in the chorda tympani nerve field. Conversely, hypergeusia tended to develop gradually in the greater petrosal nerve field. The filter paper disc test revealed a tendency for the development of hypergeusia for sweetness, saltiness, and sourness in the chorda tympani nerve field. Hypogeusia for bitterness tended to develop with increasing number of chemotherapy cycles. The glossopharyngeal nerve field exhibited the same tendencies as observed in the chorda tympani nerve field. In the greater petrosal nerve field, there was a tendency for the development of hypergeusia for sweetness, sourness, and bitterness. CONCLUSIONS: Abnormal test results were seen in half of patients after cancer chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de los Genitales Femeninos/tratamiento farmacológico , Trastornos del Gusto/inducido químicamente , Trastornos del Gusto/diagnóstico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Hidrocarburos Aromáticos con Puentes/administración & dosificación , Hidrocarburos Aromáticos con Puentes/efectos adversos , Carboplatino/administración & dosificación , Carboplatino/efectos adversos , Cobre/sangre , Femenino , Neoplasias de los Genitales Femeninos/sangre , Humanos , Hierro/sangre , Persona de Mediana Edad , Trastornos del Gusto/sangre , Taxoides/administración & dosificación , Taxoides/efectos adversos , Lengua/efectos de los fármacos , Lengua/fisiopatología , Zinc/sangre , Zinc/deficiencia
10.
Gan To Kagaku Ryoho ; 38(4): 689-92, 2011 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-21499007

RESUMEN

The subject was a 75-year-old female who was receiving paclitaxel and carboplatin(TC)chemotherapy every other week after surgery for ovarian cancer. She greatly complained of taste disorders after four cycles(of every other week administration) of TC chemotherapy. To understand how the taste disorder was caused by chemotherapy objectively, taste examinations were conducted for the patient in our department. These examinations were conducted after receiving the informed consent from the patient. The authors conducted taste examinations for the patient using serum zinc measurement, tongue cell culture, electrogustometry, and filter paper disc tests(before and after starting chemotherapy), and found that her serum zinc level fell significantly after four cycles of chemotherapy. Orally disintegrating tablets of polaprezinc were then administered to the patient, after which the subjective symptom of taste disorder improved. Her serum zinc level increased, and the electrogustometric threshold rapidly fell(an improvement). The filter paper disc test showed some improvement, particularly in the glossopharyngeal nerve and the greater petrosal nerve field.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/efectos adversos , Carnosina/análogos & derivados , Compuestos Organometálicos/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Paclitaxel/efectos adversos , Trastornos del Gusto/prevención & control , Administración Oral , Anciano , Carboplatino/administración & dosificación , Carboplatino/uso terapéutico , Carnosina/uso terapéutico , Femenino , Humanos , Estadificación de Neoplasias , Neoplasias Ováricas/patología , Paclitaxel/administración & dosificación , Paclitaxel/uso terapéutico , Trastornos del Gusto/inducido químicamente , Compuestos de Zinc/uso terapéutico
11.
J Obstet Gynaecol Res ; 36(3): 567-71, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20598039

RESUMEN

Although primary carcinoid tumor of the ovary is an extremely rare neoplasm, survival is excellent if the disease is confined to one ovary. Herein, we present a case of primary strumal carcinoid tumor of the ovary, stage IA, borderline malignancy, in a 34-year-old woman. Histological findings of the right ovary indicated higher atypical nuclei, higher mitotic rate and focal necrosis of tumorous cells in some areas, findings that are compatible with atypical carcinoid of the lung. Immunohistochemical staining was positive for synaptophysin, neuron-specific enolase, chromogranin A, Ki-67, topoisomerase IIalpha, peptide YY, and thyroglobulin. Three and a half years postoperatively, multiple bone and breast metastases were found and anticancer chemotherapy was ineffective. The results in the present case indicate that an ovarian carcinoid tumor found to be 'atypical carcinoid' according to pulmonary carcinoid criteria or immunohistochemical staining (i.e. highly positive for topoisomerase IIalpha and Ki-67) may have a poor prognosis.


Asunto(s)
Neoplasias Óseas/secundario , Neoplasias de la Mama/secundario , Tumor Carcinoide/secundario , Neoplasias Ováricas/patología , Estruma Ovárico/secundario , Adulto , Tumor Carcinoide/metabolismo , Cromogranina A/metabolismo , Femenino , Humanos , Neoplasias Ováricas/metabolismo , Estruma Ovárico/metabolismo , Sinaptofisina/metabolismo
12.
Clin Calcium ; 20(5): 672-81, 2010 May.
Artículo en Japonés | MEDLINE | ID: mdl-20445278

RESUMEN

Calcium transfer from the mother to the infant during pregnancy and lactation plays an extremely important role in the bone health of the mother and neonate. Calcium aids in bone health through all ages but is especially crucial during pregnancy and lactation. Changes in the structure and metabolism of bone during pregnancy and the early stage of postpartum are evaluated by investigating bone mineral density (BMD), bone histomorphometry and bone markers of human or animal models. The bone resorption increased at the end of pregnancy and lactation, and the bone formation increases and the bone structure is almost recovered after cessation of lactating in postpartum. Puerperal BMD remained static over the subsequent 5-10 years. If the women have a low BMD at this stage of their reproductive life, it tends not to improve over this time. Perhaps identification of this at-risk group may lead to effective interventions to reduce fracture risk in later life.


Asunto(s)
Huesos/metabolismo , Lactancia/metabolismo , Osteoporosis/etiología , Embarazo/metabolismo , Adulto , Animales , Resorción Ósea , Femenino , Fracturas Espontáneas/etiología , Fracturas Espontáneas/prevención & control , Humanos , Osteogénesis , Osteoporosis/prevención & control , Periodo Posparto/metabolismo , Ratas , Riesgo , Vitamina D/metabolismo , Adulto Joven
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