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1.
Nature ; 588(7839): 625-630, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33328640

RESUMO

Growing populations and agricultural intensification have led to raised riverine nitrogen (N) loads, widespread oxygen depletion in coastal zones (coastal hypoxia)1 and increases in the incidence of algal blooms.Although recent work has suggested that individual wetlands have the potential to improve water quality2-9, little is known about the current magnitude of wetland N removal at the landscape scale. Here we use National Wetland Inventory data and 5-kilometre grid-scale estimates of N inputs and outputs to demonstrate that current N removal by US wetlands (about 860 ± 160 kilotonnes of nitrogen per year) is limited by a spatial disconnect between high-density wetland areas and N hotspots. Our model simulations suggest that a spatially targeted increase in US wetland area by 10 per cent (5.1 million hectares) would double wetland N removal. This increase would provide an estimated 54 per cent decrease in N loading in nitrate-affected watersheds such as the Mississippi River Basin. The costs of this increase in area would be approximately 3.3 billion US dollars annually across the USA-nearly twice the cost of wetland restoration on non-agricultural, undeveloped land-but would provide approximately 40 times more N removal. These results suggest that water quality improvements, as well as other types of ecosystem services such as flood control and fish and wildlife habitat, should be considered when creating policy regarding wetland restoration and protection.


Assuntos
Conservação dos Recursos Naturais/métodos , Nitratos/isolamento & purificação , Nitratos/metabolismo , Áreas Alagadas , Agricultura , Animais , Conservação dos Recursos Naturais/economia , Política Ambiental/economia , Política Ambiental/tendências , Recuperação e Remediação Ambiental/economia , Recuperação e Remediação Ambiental/métodos , Eutrofização , Inundações/prevenção & controle , Mapeamento Geográfico , Rios , Estados Unidos , Qualidade da Água
3.
Cryo Letters ; 35(3): 162-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24997833

RESUMO

BACKGROUND: The pan-tropical genus Ardisia has more than 400 species and is of high horticultural and medicinal value. Due to overexploitation it is important to conserve the germplasm of this genus. OBJECTIVE: To investigate the feasibility and methods of cryopreservation for long-term seed storage of three Ardisia species: A. elliptica Thunb., A. brunnescens Walker, and A. virens Kurz. METHODS: We tested whether rapid desiccation can increase desiccation tolerance and cryotolerance, and whether the thawing rate can affect cryopreservation success. Seeds were subjected to three desiccation treatments: 1) activated silica gel at 25 +/- 2 degree C, and 4% relative humidity (RH); 2) saturated NaCl solution in closed jars in 25 +/- 2 degree C and 75% RH; and 3) air-drying at room conditions at 27 +/- 2 degree C and RH 60% for different desiccation durations (12h, 24h, 48h, 96h, and 196h). Seeds were then assessed for desiccation tolerance and cryotolerance after rapid thawing (direct immersion in 36 degree C water bath for 2 min) or slow thawing (at 27°C for 1 h). RESULTS: For all three species, desiccation method and duration significantly affected cryotolerance (P < 0.0001). Fast desiccation did not improve germination compared to slower desiccation (P < 0.01). Whereas A. elliptica germination was unaffected by desiccation duration, drying time significantly (P < 0.0001) affected germination percentage in the other two species especially after 48h. Although slow thawing improved cryotolerance of A. brunnescens seeds (P < 0.05), there was no significant effect of thawing rate on A. elliptica. A. virens seed did not survive cryopreservation. CONCLUSIONS: Cryopreservation protocols of Ardisia species may be species-specific and should be established for each species in the genus so that cryopreservation can be used as a successful conservation strategy.


Assuntos
Ardisia/crescimento & desenvolvimento , Criopreservação/métodos , Dessecação/métodos , Sementes/crescimento & desenvolvimento , Germinação , Umidade , Sílica Gel/química , Água/química
4.
J Pediatr Surg ; 33(5): 787-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9607503

RESUMO

Scrotal masses in young children are often caused by hydrocoeles and hernias. When they arise from the testis, testicular tumor or orchitis, although rare in this age group, is often the diagnosis. Cystic dysplasia of the testis, a rare condition frequently associated with renal anomalies, is another possible differential diagnosis. Herein the authors describe a case in which cystic dysplasia of the testis is associated with ipsilateral renal agenesis as well as high anorectal anomalies.


Assuntos
Anormalidades Múltiplas/diagnóstico , Canal Anal/anormalidades , Cistos/patologia , Rim/anormalidades , Reto/anormalidades , Doenças Testiculares/patologia , Pré-Escolar , Cistos/diagnóstico , Cistos/cirurgia , Diagnóstico Diferencial , Humanos , Rim/diagnóstico por imagem , Masculino , Orquiectomia , Doenças Retais/congênito , Doenças Retais/diagnóstico , Doenças Testiculares/diagnóstico , Doenças Testiculares/cirurgia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/patologia , Ultrassonografia
5.
Artigo em Inglês | MEDLINE | ID: mdl-3738612

RESUMO

Taeniasis is a major public health problem among the aboriginal populations on Taiwan, and is highly prevalent and wide spread in the mountain areas of 10 Counties. Over 27,000 cases of tapeworm infection are estimated influencing the health and economy in the endemic areas. A treatment of taeniasis with mebendazole and praziquantel followed by a re-treatment with atabrine has been done in the field trial, and confirmed that praziquantel is highly effective agent against tapeworm infection, but mebendazole is not. Based upon experiments reported here praziquantel in a single dose of 150 mg, and 450 mg are highly effective against taeniasis and hymenolepiasis respectively.


Assuntos
Mebendazol/uso terapêutico , Praziquantel/uso terapêutico , Teníase/tratamento farmacológico , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quinacrina/uso terapêutico
6.
IEEE Int Conf Rehabil Robot ; 2011: 5975423, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22275624

RESUMO

This paper is the continuation of a work presented at ICORR 07, in which we discussed the possibility of improving eye-hand coordination in children diagnosed with this problem, using a robotic mapping from a haptic user interface to a virtual environment. Our goal is to develop, implement and refine a system that will assess and improve the eye-hand coordination and grip strength in children diagnosed with poor graphomotor skills. A detailed analysis of patters (e.g., labyrinths, letters and angles) was conducted in order to select three very distinguishable levels of difficulty that could be included in the system, and which would yield the greatest benefit in terms of assessment of coordination and strength issues as well as in training. Support algorithms (position, force, velocity, inertia and viscosity) were also developed and incorporated into the tasks in order to introduce general computer assistance to the mapping of the user's movements to the computer screen without overriding the user's commands to the robotic device. In order to evaluate performance (given by %accuracy and time) of the executed tasks, a sophisticated evaluation function was designed based on image analysis and edge detection algorithms. This paper presents the development of the haptic tasks, the various assistance algorithms, the description of the evaluation function and the results of a study implemented at the Motor Development Clinic at Cal Poly Pomona. The results (Accuracy and Time) of this function are currently being used as inputs to an Intelligent Decision Support System (described in), which in turn, suggests the next task to be executed by the subject based on his/her performance.


Assuntos
Olho/fisiopatologia , Mãos/fisiologia , Movimento/fisiologia , Robótica/instrumentação , Robótica/métodos , Algoritmos , Criança , Humanos
8.
Bull World Health Organ ; 38(3): 469-77, 1968.
Artigo em Inglês | MEDLINE | ID: mdl-5302337

RESUMO

In certain areas of Sabah, East Malaysia, local houses are frequently built without walls or with incomplete walls. Also, the people in these areas often refuse permission for their houses to be sprayed inside with insecticide (DDT). These special conditions are the reason for the persistence of malaria transmission under a WHO malaria eradication programme.Field trials were conducted in specially constructed huts, similar to the local houses, in which all-night collections of mosquitos were made, both those biting human baits and those resting on walls, in order to determine (1) the effectiveness of spraying DDT in houses without, or with incomplete, walls; and (2) the best way to protect people against mosquito bites with DDT-spraying where the house-owners have refused indoor spraying.The results indicate that (1) as expected, DDT-spraying inside a hut with incomplete walls is less effective than in a hut with complete walls, especially 6 months or more after spraying; (2) external spraying of walls with DDT at double the normal dose (i.e., 4 g/m(2)) greatly reduced contacts between man and mosquito and thereby limited transmission of malaria.


Assuntos
DDT/administração & dosagem , Habitação , Controle de Mosquitos , Animais , Anopheles/efeitos dos fármacos , Humanos , Malária/prevenção & controle , Malásia
9.
Hunan Yi Ke Da Xue Xue Bao ; 26(1): 70-2, 2001 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-12536624

RESUMO

UNLABELLED: To explore the etiology and different methods of diagnosis for 33 cases of small intestinal hemorrhage, which were confirmed by surgery and/or pathology. METHODS: 33 cases of small intestinal hemorrhage were diagnosed by endoscopy, barium studies, radionucleotide scanning, angiograpy, exploratory laparotomy and intraoperative colonscopy, which were confirmed by surgery and/or pathology. RESULTS: Small intestinal tumors were found in 13 cases (39.39%), Leiomyoma in 8; infectious diseases in 8(24.24%); Meckel's diverticulum in 7(21.21%); and vascular malformation in 3(9.1%) and others in 2(6.06%). Among them, black stool (42.42%) is the most commonly seen. The common clinical presentation was middle-anemia and patients with unexplained abdominal pain (36.36%). Radionucleotide scanning was positive in 5 out of 7 cases, and all of five were Meckel's diverticulum. Endoscopy revealed 5 out of 20 cases. Exploratory laparotomy was performed in 6, 3 were found to have some lesions, and the other 3 were diagnosed by intraoperative colonscopy. CONCLUSIONS: Tumor is the nost common cause of small intestinal hemorrhage, mied anemia and black stool are the common clinical presentations, Radionucleotide scanning is one of the most useful diagnostic methods for Meckel's diverticulum and intraoperative colonscopy could elevate veracity of diagnosis.


Assuntos
Hemorragia Gastrointestinal/diagnóstico , Neoplasias Intestinais/diagnóstico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Hemorragia Gastrointestinal/etiologia , Humanos , Neoplasias do Íleo/complicações , Neoplasias do Íleo/diagnóstico , Neoplasias Intestinais/complicações , Neoplasias do Jejuno/complicações , Neoplasias do Jejuno/diagnóstico , Leiomioma/complicações , Leiomioma/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Ophthalmic Res ; 28(1): 57-63, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8726678

RESUMO

Glucose and phosphorus metabolism in mature (8-month-old) rat lenses were examined with NMR spectroscopy. Nondiabetic mature lenses contained sorbitol-3-phosphate (S3P) and fructose-3-phosphate (F3P) which were absent from young (1- to 2-month-old) normal rat lenses. The concentrations of these two phosphates can be changed through (1) diabetes induction with streptozotocin - this results in a dramatic increase in both compounds; and (2) oral dosing with a drug known to prevent sorbitol production - both metabolites disappeared. When normal mature lenses were incubated in 35.5 mM 13C1-glucose, both 13C1-lactate and 13C3-lactate were produced. Preservation of the 13C label at C1 is likely through the formation of 13C1-S3P and -F3P, which were then split through an aldolase-like mechanism into two 3-carbon compounds, one an unlabeled glycerol and the other 13C1-alpha-glycerophosphate (from S3P) and 13C1-dihydroxyacetone phosphate (from F3P). These reactions can contribute to the increase in alpha-glycerophosphate observed in both the streptozotocin-induced diabetic lenses and lenses incubated in high glucose.


Assuntos
Envelhecimento/metabolismo , Frutosefosfatos/metabolismo , Hexosefosfatos/metabolismo , Cristalino/metabolismo , Animais , Diabetes Mellitus Experimental/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley , Valores de Referência
11.
Exp Eye Res ; 61(4): 479-86, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8549689

RESUMO

Diabetic lens glucose metabolism in vivo can be altered by a number of exogenous substrates. We have chosen two, one a glucose epimer (mannose) and the other a glycolytic intermediate (pyruvate), to demonstrate the possibility of this approach. D(+)-Mannose is a D(+)-glucose epimer but in lenses incubated in 35.5 mM mannose, no mannitol (the sorbitol equivalent) was detected, while both lactate production and 31P profile appeared normal. Mannose therefore is a good glucose substitute causing no polyol formation. Mannose metabolism in the rat lens in vivo was then examined. Diabetic rats fed mannose-enriched diet over a period of 14 days showed retardation of changes in 31P metabolites, specifically the levels of phosphorylcholine and glycerophosphorylcholine, suggesting a protective effect. Rat lenses incubated in 35.5 mM glucose in the presence of 5 mM pyruvate (pyr) showed 50% lower sorbitol than without pyr. With 5 mM pyr in the drinking water, i.e. pretreatment in vivo during a 3-day diabetes induction period, the diabetic rat lens accumulated acetate and alanine when incubated in the presence of pyr. The decrease in sorbitol was most likely due to a lower glucose flux rather than an increased polyol dehydrogenase activity. Increasing glucose concentration from 5.5 to 35.5 mM or provision of exogenous pyr both caused an intermediate increase in O2 consumption in the normal lens; a maximal activity was reached with both 35.5 mM glucose and 5 mM pyruvate in the incubating medium. In the diabetic lens, O2 consumption could reach the intermediate but not the maximal level. Dietary pyr pre-treatment also prevented normal and diabetic lenses from maximal pyr-stimulated O2 consumption. The NMR and O2 consumption data together indicated activation of alanine dehydrogenase and saturation of Krebs cycle. It appears that dietary supplement of mannose can preserve 31P membrane metabolites in the diabetic lens. Mannose can be used in conjunction with hypoglycemic therapy for the management of diabetic cataract. In addition, pyruvate may be effective in enhancing lens energy metabolism and lower sorbitol production.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo , Cristalino/metabolismo , Manose/metabolismo , Piruvatos/metabolismo , Animais , Diabetes Mellitus Experimental/prevenção & controle , Espectroscopia de Ressonância Magnética , Masculino , Manose/uso terapêutico , Técnicas de Cultura de Órgãos , Consumo de Oxigênio/efeitos dos fármacos , Piruvatos/uso terapêutico , Ratos , Ratos Sprague-Dawley
12.
Histopathology ; 31(6): 552-4, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9447387

RESUMO

AIMS: To report an unusual instance of intravascular lymphomatosis presented with encephalomyelitis and reactive haemophagocytic syndrome. There was no skin involvement. The diagnosis was made on a renal biopsy. METHODS AND RESULTS: The marrow smear was air dried and stained with Diff-Quik. The tissue sections were stained with haematoxylin and eosin. Masson trichrome, periodic acid-Schiff's reagent, Elastic van Gieson's stain, modified hexamine-silver technique and Martius scarlet blue. Immunohistochemistry for CD45, CD20, CD45RO, Factor VIII related antigen, CD31 and CD34 was performed on paraffin-processed tissue. The marrow smear showed active haemophagocytosis in the histiocytes. The renal biopsy showed intravascular lymphomatosis with tumour cells positive for CD45 and CD20. CONCLUSION: The possibility of intravascular lymphomatosis should be considered in patients with reactive haemophagocytic syndrome where the underlying cause cannot be found after thorough investigation.


Assuntos
Encefalomielite/diagnóstico , Histiocitose de Células não Langerhans/diagnóstico , Neoplasias Renais/diagnóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Adulto , Diagnóstico Diferencial , Encefalomielite/patologia , Feminino , Histiocitose de Células não Langerhans/patologia , Humanos , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/patologia , Linfoma Difuso de Grandes Células B/patologia
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