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1.
Science ; 382(6671): 679-683, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37943897

RESUMO

Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.


Assuntos
Variação Biológica da População , Herbivoria , Defesa das Plantas contra Herbivoria , Plantas , Ecossistema , Filogenia , Animais , Evolução Biológica
2.
Mymensingh Med J ; 32(2): 412-420, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37002752

RESUMO

The study was intended to evaluate efficacy of Intra-arterial nitroglycerin through the sheath at the end of a transradial procedure to preserve the patency of the radial artery. This prospective observational study was done in the Department of Cardiology, National Institute of Cardiovascular Diseases (NICVD), Dhaka, Bangladesh from May 2017 to April 2018, by including a total 200 patients undergoing coronary procedures (CAG and / or PCI) through TRA. RAO was defined as an absence of antegrade flow or monophasic flow or invert flow on Doppler study. In this study 102 patients (Group I) received 200 mcg intra-arterial nitroglycerine, prior to trans-radial sheath removal. Another 98 patients (Group II) did not receive intra-arterial nitroglycerine prior to trans-radial sheath removal. Conventional haemostatic compression methods were applied (average 2 hours) in both groups of patients. Evaluation of radial arterial arterial blood flow by colour Doppler study was done on next day after the procedure in both groups. Results of this study in which RAO was determined by vascular doppler study showed that frequency of radial artery occlusion were 13.5% one day after transradial coronary procedures. We found the incidence was 8.8% vs. 18.4%, (p=0.04) in Group I and Group II respectively. The incidence of RAO was significantly lower in post procedural nitroglycerine group. From multivariate logistic regression analysis diabetes mellitus (p = 0.02), hemostatic compression time for more than 02 hours after sheath removal (p = <0.001) and procedure time (p = 0.02) was predictors of RAO. So, the administration of nitroglycerin at the end of a transradial catheterization reduced the incidence of RAO, as shown by 1 day after the radial procedure by doppler ultrasound.


Assuntos
Arteriopatias Oclusivas , Intervenção Coronária Percutânea , Humanos , Nitroglicerina/uso terapêutico , Artéria Radial/diagnóstico por imagem , Intervenção Coronária Percutânea/efeitos adversos , Cateterismo Cardíaco/métodos , Bangladesh , Ultrassonografia Doppler/efeitos adversos , Ultrassonografia Doppler/métodos , Arteriopatias Oclusivas/etiologia , Arteriopatias Oclusivas/prevenção & controle , Arteriopatias Oclusivas/epidemiologia
3.
Phys Rev Lett ; 129(14): 142502, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36240396

RESUMO

The root mean square radii of the proton density distribution in ^{16-24}O derived from measurements of charge changing cross sections with a carbon target at ∼900A MeV together with the matter radii portray thick neutron skin for ^{22-24}O despite ^{22,24}O being doubly magic. Imprints of the shell closures at N=14 and 16 are reflected in local minima of their proton radii that provide evidence for the tensor interaction causing them. The radii agree with ab initio calculations employing the chiral NNLO_{sat} interaction, though skin thickness predictions are challenged. Shell model predictions agree well with the data.


Assuntos
Nêutrons , Prótons , Carbono
4.
Phys Rev Lett ; 124(22): 222504, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32567915

RESUMO

We report the measurement of reaction cross sections (σ_{R}^{ex}) of ^{27,29}F with a carbon target at RIKEN. The unexpectedly large σ_{R}^{ex} and derived matter radius identify ^{29}F as the heaviest two-neutron Borromean halo to date. The halo is attributed to neutrons occupying the 2p_{3/2} orbital, thereby vanishing the shell closure associated with the neutron number N=20. The results are explained by state-of-the-art shell model calculations. Coupled-cluster computations based on effective field theories of the strong nuclear force describe the matter radius of ^{27}F but are challenged for ^{29}F.

5.
Phys Rev Lett ; 124(10): 102501, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32216444

RESUMO

Interaction cross sections for ^{42-51}Ca on a carbon target at 280 MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number N=28. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and mean field calculations point out that this anomalous enhancement of the nuclear size beyond N=28 results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare ^{48}Ca core in Ca isotopes beyond N=28.

6.
Indian J Nephrol ; 26(4): 244-51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27512295

RESUMO

There is no published study from India on hepatitis C virus (HCV) treatment in dialysis patients. Patients on dialysis with HCV infection treated with pegylated interferon (Peg-INF) monotherapy were studied. All patients were subjected to HCV-polymerase chain reaction, viral load, genotype, and liver biopsy. Quantitative HCV-RNA was performed monthly. Patients with genotype 1 and 4 were given 12 month therapy while those with genotypes 2 and 3 were given 6 months therapy. Response was classified as per standard criteria of rapid virological response (RVR), early virological response (EVR), end of treatment response (ETR), and sustained virological response (SVR). A total of 85 patients were treated. Mean age was 35.2 ± 10.5 (range 15-67) years, and 77.6% were males. HCV genotypes were 1 in 40.9%, 2 in 12%, 3 in 36.1%, 4 in 3.6%, and others in 7.2%. Mean viral load was 10(6) copies/mL. Mean liver biopsy grade was 4 ± 1.7 and stage 0.8 ± 0.8. Mean time from diagnosis of HCV infection and the treatment start was 10.7 ± 14.3 months. One patient died of unrelated illness, one was lost to follow-up, and three could not sustain treatment due to cost. Forty-three of the 80 (54%) patients had RVR while 49 (61%) patients had EVR and ETR. There was no difference in term of RVR related to genotype. Fifty -four percentage had SVR. Mild flu-like symptoms were seen in all patients. Sixty-four (80%) patients required increase in erythropoietin doses. Twenty-eight (35%) patients developed leukopenia (three treatment-limiting) and 16 (20%) developed thrombocytopenia (one treatment-limiting). Five patients developed tuberculosis, five bacterial pneumonia, and one bacterial knee monoarthritis. None of the patients developed depression. Our study concludes that Peg-INF monotherapy resulted in 54% RVR and SVR in dialysis patients with HCV infection. Therapy was well-tolerated with minimal side effects. There was no effect of viral genotype on response to therapy.

7.
Indian J Nephrol ; 26(3): 212-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27194838

RESUMO

Post transplant lymphoproliferative disorder include a spectrum of conditions occurring in immunosuppressed post transplant recipients, lymphoma being the most ominous. (18)F-fludeoxyglucose positron emission tomography with computed tomography CT) is the current imaging gold standard for lymphoma imaging as it allows both morphological and functional assessment. CT and/or conventional magnetic resonance imaging (MRI) are used for morphological evaluation in transplant recipients. Integrating diffusion weighted imaging with apparent diffusion coefficient analysis in MRI protocol enhances its sensitivity and may prove invaluable in response assessment in transplant recipients.

8.
Carbohydr Polym ; 138: 215-21, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26794755

RESUMO

In this existing experimental work, water soluble PDP polysaccharides were secluded from Pithecellobium dulce (Roxb.) Benth. seeds. The physicochemical properties were analyzed in terms of swelling power, solubility, pH and water holding capacity. Micromeretic studies proved the polysaccharide may be used a potential pharmaceutical adjuvant. The polysaccharide was characterized by FT-IR, SEM, TGA and NMR techniques. Methylation analysis confirmed that the polysaccharide is composed of Arabinose (Araf) units. The chemical shifts of anomeric proton region were found in the region of 4.4-5.5ppm. Thermogravimetric analysis showed that PDP polysaccharide was thermally stable. The in vitro antioxidant capacities of the polysaccharide were investigated in terms of scavenging of hydroxyl radicals, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radicals, hydrogen peroxide (H2O2) and reducing power assay. The polysaccharide fractions showed activity in a concentration dependent manner which was comparable to the standard, ascorbic acid.


Assuntos
Fabaceae/metabolismo , Polissacarídeos/química , Água/química , Sequestradores de Radicais Livres/química , Concentração de Íons de Hidrogênio , Radical Hidroxila/química , Microscopia Eletrônica de Varredura , Sementes/metabolismo , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
9.
Artigo em Inglês | MEDLINE | ID: mdl-26651640

RESUMO

We report here energetic (>100 keV) negative hydrogen ions (H(-)) generated in the interaction of moderately intense (10(18) W cm(-2)) ultrashort laser pulses (45 fs) with transparent hydrogen containing solid targets. An unambiguous and consistent detection of negative hydrogen ions, with a flux of 8×10(11)H(-) ions/sr, has been observed in every single laser shot, using a Thomson parabola ion spectrograph. Simple estimates based on charge transfer cross sections match well with experimental observations. Our method offers the implementation of an intense, ultrashort laser based negative-ion source at a higher repetition rate, which can be important for various applications.

10.
Artigo em Inglês | MEDLINE | ID: mdl-25215835

RESUMO

We report on the proton acceleration studies from thin metallic foils of varying atomic number (Z) and thicknesses, investigated using a 45 fs, 10 TW Ti:sapphire laser system. An optimum foil thickness was observed for efficient proton acceleration for our laser conditions, dictated by the laser ASE prepulse and hot electron propagation behavior inside the material. The hydrodynamic simulations for ASE prepulse support the experimental observation. The observed maximum proton energy at different thicknesses for a given element is in good agreement with the reported scaling laws. The results with foils of different atomic number Z suggest that a judicious choice of the foil material can enhance the proton acceleration efficiency, resulting into higher proton energy.


Assuntos
Lasers , Prótons , Radiação , Compostos de Alumínio , Óxido de Alumínio , Simulação por Computador , Cobre , Elétrons , Compostos de Ouro , Hidrodinâmica , Níquel , Tantálio , Titânio
11.
Transpl Infect Dis ; 16(5): 838-42, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25040057

RESUMO

Renal transplant recipients may present with intracranial space-occupying lesions (SOLs) due to infections as well as a post-transplant lymphoproliferative disorder (PTLD). Here, we discuss a renal transplant recipient who presented with neurologic symptoms and magnetic resonance imaging (MRI) of the brain showed multiple focal SOLs. Tuberculosis (TB), toxoplasmosis, nocardiosis, fungal infections, and PTLD were considered in the differential diagnosis. MRI spectroscopy was suggestive of an infectious cause, such as toxoplasmosis or TB. Serologic tests using Toxoplasma were negative. A brain biopsy followed by immunohistochemical staining using Toxoplasma antibody demonstrated multiple intravascular cysts of toxoplasma. This case highlights the diagnostic dilemma in an immunocompromised patient with multiple focal brain lesions, especially in areas where TB is endemic.


Assuntos
Transplante de Rim/efeitos adversos , Toxoplasmose Cerebral/diagnóstico , Tuberculoma Intracraniano/diagnóstico , Adulto , Infecções Fúngicas do Sistema Nervoso Central/diagnóstico , Diagnóstico Diferencial , Humanos , Índia , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/etiologia , Imageamento por Ressonância Magnética , Masculino , Nocardiose/diagnóstico , Toxoplasmose Cerebral/tratamento farmacológico
13.
Afr Health Sci ; 11(1): 128-33, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21572868

RESUMO

BACKGROUND: Cold chain maintenance is an essential activity to maintain the potency of vaccines and to prevent adverse events following immunization. One baseline study highlighted the unsatisfactory cold chain status in city of Kolkata in India. OBJECTIVES: To assess the changes which occurred in the cold chain status after the intervention undertaken to improve the status and also to assess the awareness of the cold chain handlers regarding cold chain maintenance. METHODS: Intervention consisted of reorganization of cold chain points and training of health manpower in Kolkata Municipal area regarding immunization and cold chain following the guidelines as laid by Govt of India. Reevaluation of cold chain status was done at 20 institutions selected by stratified systematic random sampling after the intervention. The results were compared with baseline survey. RESULTS: Significant improvement had been observed in correct placing of cold chain equipment, maintenance of stock security, orderly placing of ice packs, diluents and vaccines inside the equipment, temperature recording and maintenance. But awareness and skill of cold chain handlers regarding basics of cold chain maintenance was not satisfactory. CONCLUSIONS: The success of intervention included significant improvement of cold chain status including creation of a designated cold chain handler. The gaps lay in non-availability of non-electrical cold chain equipment and separate cold chain room, policy makers should stress. Cold chain handlers need reorientation training regarding heat & cold sensitive vaccines, preventive maintenance and correct contingency plan.


Assuntos
Armazenamento de Medicamentos/normas , Refrigeração/normas , Vacinas/provisão & distribuição , Temperatura Baixa , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Índia , Competência Profissional , Avaliação de Programas e Projetos de Saúde , Garantia da Qualidade dos Cuidados de Saúde , Refrigeração/métodos , População Urbana
14.
J Indian Med Assoc ; 109(10): 759-61, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22482328

RESUMO

Choroidal haemangioma is a benign tumour with visual acuity diminution due to subretinal fluid accumulation. There are many modalities of treatment of this visually disabling syndrome, some of them being argon laser photocoagulation, cryotherapy, external beam irradiation, proton beam radiotherapy, episcleral plaque radiotherapy and transpupillary thermotherapy. Another new modality of treatment with remarkable success rate is photodynamic therapy. In this modality a photosensitiser is injected intravenously followed by irradiation of a specific wave length for a specified time period. The photosensitiser concentrates within the vascular channels and after irradiation these channels are irreversibly obliterated. A 62 years old female patient of choroidal haemangioma, who presented in eye outpatient department was treated with the standard protocol used for photodynamic therapy. On follow-up of this patient it was found that there was improvement in the visual acuity from 6/12 in the left eye (affected eye) to 6/9. Not only was there an improvement in the visual acuity but there was anatomical improvement too as was evident by regressed cystoid macular oedema and circumscribed choroidal haemangioma. After six months of follow-up there was no leakage of dye with digital fluorescein angiography and indocyanine green.


Assuntos
Neoplasias da Coroide/diagnóstico , Neoplasias da Coroide/tratamento farmacológico , Hemangioma/diagnóstico , Hemangioma/tratamento farmacológico , Fotoquimioterapia , Feminino , Humanos , Pessoa de Meia-Idade
15.
Water Sci Technol ; 61(10): 2563-73, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20453329

RESUMO

Low-temperature carbonization (LTC) of coal generates highly complex wastewater warranting stringent treatment. Developing a techno-economically viable treatment facility for such wastewaters is a challenging task. The paper discusses a case study pertaining to an existing non-performing effluent treatment plant (ETP). The existing ETP comprising an ammonia stripper followed by a single stage biological oxidation was unable to treat 1,050 m(3)/d of effluent as per the stipulated discharge norms. The treated effluent from the existing ETP was characterized with high concentrations of ammonia (75-345 mg N/l), COD (313-1,422 mg/l) and cyanide (0.5-4 mg/l). Studies were undertaken to facilitate recycling/reuse of the treated effluent within the plant. A second stage biooxidation process was investigated at pilot scale for the treatment of the effluent from the ETP. This was further subjected to tertiary treatment with 0.5% dose of 4% hypochlorite which resulted in effluent with pH: 6.6-6.8, COD: 73-121 mg/l, and BOD(5):<10 mg/l. Phenol, cyanide and ammonia were below detectable limits and the colourless effluent was suitable for recycle and reuse. Thus, a modified treatment scheme comprising ammonia pre-stripping followed by two-stage biooxidation process and a chemical oxidation step with hypochlorite at tertiary stage was proposed for recycle/reuse of LTC wastewater.


Assuntos
Combustíveis Fósseis , Eliminação de Resíduos Líquidos/métodos , Amônia/análise , Carbono , Carvão Mineral , Coque , Conservação dos Recursos Naturais , Desenho de Equipamento , Gases/análise , Gases/isolamento & purificação , Metais Pesados/análise , Naftalenos/análise , Oxirredução , Projetos Piloto , Purificação da Água/métodos
16.
Oncogene ; 28(26): 2456-65, 2009 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-19430492

RESUMO

The Cul4A gene, which encodes a core component of a cullin-based E3 ubiquitin ligase complex, is overexpressed in breast and hepatocellular cancers. In breast cancers, overexpression of Cul4A strongly correlates with poor prognosis. In addition, Cul4A is required for early embryonic development. The early lethality of mouse embryos prevented a detailed analysis of the functions of Cul4A. Here, we used a strain of mice carrying floxed alleles of Cul4A to study its role in cell division, in vitro and in vivo. Embryonic fibroblasts (MEFs) show a severe deficiency in cell proliferation after deletion of Cul4A. We observed that the Cul4A protein is abundantly expressed in the brain, liver and the mammary tissue of pregnant mice. Deletion of Cul4A in the liver impairs hepatocyte proliferation during regeneration after carbon tetrachloride (CCl(4))-induced injury. The Cul4A-deleted cells are slow in entering the S phase, and are deficient in progressing through the early M phase. Several cell-cycle regulators, including p53 and p27Kip1, are deregulated in the Cul4A-deleted cells. Expression of a dominant negative mutant of p53 causes significant reversal of the proliferation defects in Cul4A-deleted cells. The Cul4A-deleted cells show an aberrant number of centrosome, multipolar spindles and micronuclei formation. Furthermore, those cells are sensitive to UV irradiation and show reduced levels of unscheduled DNA synthesis (UDS). Together, our observations indicate that Cul4A is required for efficient cell proliferation, control of centrosome amplification and genome stability.


Assuntos
Proteínas Culina/genética , Instabilidade Genômica , Deleção de Sequência , Animais , Tetracloreto de Carbono/toxicidade , Divisão Celular , Linhagem Celular , Proliferação de Células , Centrossomo/metabolismo , Instabilidade Cromossômica , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , DNA/biossíntese , Reparo do DNA , Hepatócitos/patologia , Humanos , Fígado/efeitos dos fármacos , Fígado/lesões , Fígado/patologia , Masculino , Camundongos , Fase S , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta
17.
J Environ Sci Eng ; 49(3): 207-10, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18476445

RESUMO

Koradi Thermal Power Station requires 1-1.2 lakh m3 of water per day and pond No. 3 is the source of water supply of Koradi Thermal Power Station. This Pond No. 3 is being replenished by Pench Canal water, but water undergoes significant changes in quality after entering Pond No. 3 and hence this aspect may be crucial for raw water intake at Water Treatment Plant Stg-II of Koradi Thermal Power Station. Therefore, an attempt has been made to evaluate the change in water quality on the basis of Strong Acid Cation Exchanger Effluent Conductivity and its impact on demineralised water treatment plant.


Assuntos
Monitoramento Ambiental/métodos , Purificação da Água/métodos , Cátions , Conservação dos Recursos Naturais , Ácido Clorídrico/química , Concentração de Íons de Hidrogênio , Resíduos Industriais , Modelos Químicos , Sais/química , Temperatura , Eliminação de Resíduos Líquidos , Água/análise , Movimentos da Água , Poluentes da Água , Abastecimento de Água
18.
Indian J Pediatr ; 73(6): 529-30, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16816518

RESUMO

A 10-month-old female child presented with intermittent high grade fever, pain and diffuse swelling in the left knee joint with history of ecchymosis in different areas of the body. There was radiological features of acute osteomyelitis, low fibrinogen level and bacteremia due to the presence of coagulase positive staphylococcus aureus. The child responded nicely to the treatment for acute osteomyelitis and congenital hypofibrinogenemia. So, in congenital hypofibrinogenemia, a joint swelling might be a resultant of an acute osteomyelitis, not mere hemarthrosis.


Assuntos
Afibrinogenemia/complicações , Osteomielite/microbiologia , Infecções Estafilocócicas/complicações , Staphylococcus aureus , Doença Aguda , Afibrinogenemia/terapia , Antibacterianos/uso terapêutico , Fator VIII/uso terapêutico , Feminino , Fibrinogênio/uso terapêutico , Humanos , Lactente , Osteomielite/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico
19.
J Obstet Gynaecol ; 26(4): 291-6, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16753674

RESUMO

This paper reviews the patterns of occurrence, measurement and the effect of birth weight discordance on fetal and neonatal mortality in multiple pregnancies (twins and triplets). Birth weight discordance is fairly common among multiple pregnancies, and about one-quarter of the twin deliveries are affected by a birth weight discordance of 15%, while nearly 5% of twin gestations experience severe discordance (>or= 35%). Factors influencing birth weight discordance are exaggerated in triplet deliveries. Approximately 20% of triplet sets experience a birth weight discordance of 25 - 35% and nearly 10% experience severe forms of discordance. Frequencies of discordant sets at >25% discordance along the range of birth weight deciles show an inverse logarithmic relationship in twins, while the best-fit function in triplets is polynomial. Birth weight discordance is significantly associated with both fetal and neonatal mortality. Neonatal demise among the severely discordant smaller twin is significantly more frequent than in a non-discordant smaller twin. The magnitude of the effect is greater when one or both of the discordant twins are concomitantly small for gestational age.


Assuntos
Peso ao Nascer , Gravidez Múltipla , Feminino , Mortalidade Fetal , Humanos , Mortalidade Infantil , Recém-Nascido , Gravidez , Resultado da Gravidez , Trigêmeos , Gêmeos
20.
Indian J Public Health ; 49(4): 256-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16479915

RESUMO

This study was carried out among the Private Allopathic Medical Practitioners (PMPs) at Khardah Municipal area (West Bengal) to find out their perception & practice about management protocol of diseases like acute respiratory infections and diarrhoel diseases in children, malaria and tuberculosis. Data was collected by interviewing the PMPs with pre-designed open-ended questionnaire. It was supplemented by analysing sample prescriptions of the same diseases. The study revealed that PMPs knowledge and practice were not at par with national guidelines. The need for periodic sensitization of PMPs regarding national disease control programme was emphasized.


Assuntos
Doenças Transmissíveis/terapia , Conhecimentos, Atitudes e Prática em Saúde , Médicos , Padrões de Prática Médica , Criança , Proteção da Criança , Controle de Doenças Transmissíveis , Estudos Transversais , Humanos , Índia , Guias de Prática Clínica como Assunto , Setor Privado
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