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1.
J Dent Res ; 101(9): 1046-1054, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35403466

RESUMO

Tobacco use is a well-established risk factor for multiple adverse oral conditions. Few nationally representative oral health data sets encompass the current diversity of tobacco and nicotine products. This investigation examines the validity of oral health measures in the Population Assessment of Tobacco and Health (PATH) Study to assess relationships between tobacco use and oral health. Cross-sectional data from PATH Study wave 4 (N = 33,643 US adults, collected 2016-2018) were used to obtain estimates for 6 self-reported oral conditions (e.g., bone loss around teeth, tooth extractions) and compared with analogous estimates from the National Health and Nutrition Examination Survey (NHANES) cycle 2017-2018 (N = 5,856). Within the PATH Study, associations were calculated between tobacco use status and lifetime and past 12-mo experience of adverse oral conditions using survey-weighted multivariable logistic regression. Nationally representative estimates of oral conditions between the PATH Study and NHANES were similar (e.g., ever-experience of bone loss around teeth: PATH Study 15.2%, 95% CI, 14.4%-15.9%; NHANES 16.6%, 95% CI, 14.9%-18.4%). In the PATH Study, combustible tobacco smoking was consistently associated with lifetime and past 12-mo experience of adverse oral health (e.g., exclusive cigarette smoking vs. never tobacco use, adjusted odds ratio [AOR] for loose teeth in past 12 mo: 2.02; 95% CI, 1.52-2.69). Exclusive smokeless tobacco use was associated with greater odds of loose teeth (AOR, 1.93; 95% CI, 1.15-3.26) and lifetime precancerous lesions (AOR, 3.85; 95% CI, 1.73-8.57). Use of other noncigarette products (e.g., pipes) was inconsistently associated with oral health outcomes. PATH Study oral health measures closely align with self-reported measures from NHANES and are internally concurrent. Observed associations with tobacco use and the ability to examine emerging tobacco products support application of PATH Study data in dental research, particularly to examine potential oral health effects of novel tobacco products and longitudinal changes in tobacco use behaviors.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Adulto , Estudos Transversais , Humanos , Inquéritos Nutricionais , Saúde Bucal , Nicotiana , Estados Unidos/epidemiologia
2.
BMC Public Health ; 21(1): 1920, 2021 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-34686158

RESUMO

BACKGROUND: Adverse childhood experiences (ACEs) increases vulnerability to externalising disorders such as substance misuse. The study aims to determine the prevalence of ACEs and its association with substance misuse. METHODS: Data from the Consortium on Vulnerability to Externalising Disorders and Addictions (cVEDA) in India was used (n = 9010). ACEs were evaluated using the World Health Organisation (WHO) Adverse Childhood Experiences International Questionnaire whilst substance misuse was assessed using the WHO Alcohol, Smoking and Substance Involvement Screening Test. A random-effects, two-stage individual patient data meta-analysis explained the associations between ACEs and substance misuse with adjustments for confounders such as sex and family structure. RESULTS: 1 in 2 participants reported child maltreatment ACEs and family level ACEs. Except for sexual abuse, males report more of every individual childhood adversity and are more likely to report misusing substances compared with females (87.3% vs. 12.7%). In adolescents, family level ACEs (adj OR 4.2, 95% CI 1.5-11.7) and collective level ACEs (adj OR 6.6, 95% CI 1.4-31.1) show associations with substance misuse whilst in young adults, child level ACEs such as maltreatment show similar strong associations (adj OR 2.0, 95% CI 1.1-3.5). CONCLUSION: ACEs such as abuse and domestic violence are strongly associated with substance misuse, most commonly tobacco, in adolescent and young adult males in India. The results suggest enhancing current ACE resilience programmes and 'trauma-informed' approaches to tackling longer-term impact of ACEs in India. FUNDING: Newton Bhabha Grant jointly funded by the Medical Research Council, UK (MR/N000390/1) and the Indian Council of Medical Research (ICMR/MRC-UK/3/M/2015-NCD-I).


Assuntos
Experiências Adversas da Infância , Maus-Tratos Infantis , Violência Doméstica , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
3.
Int J Colorectal Dis ; 36(1): 161-167, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32929529

RESUMO

AIM: The PICO (Smith & Nephew, UK) dressing is a single use negative pressure wound therapy (NPWT) system that is designed to be used for up to 7 days for closed wounds. We aimed to assess its use for stoma closure wounds. METHOD: We conducted a retrospective analysis of stoma reversal wounds from April 2018 to June 2019. The wound was partially closed with an absorbable subcutaneous suture in a purse-string fashion. A 15 cm × 15 cm PICO dressing was applied directly over this wound. A control group who had received partial purse string closure with packing over the same time period was identified. Patients were contacted and information collected using a questionnaire. The primary outcome measure was the number of visits for dressing changes in the community. Further information was collected about length of stay, time to resolution of pain and return to work. RESULTS: On average, the patients with PICO dressings attended the community nurses 1.9 times. The patients in the PICO group stated it took 1-2 weeks to return to full work/daily activities. The control group averaged attending the community nurse 11.9 times, and 33% had not returned to work/daily activities in 1-2 weeks. CONCLUSION: Those who had a PICO dressing required fewer visits to the community nurse and the majority were able to return to work or resume usual activities within 1 to 2 weeks. This pilot study suggests that negative pressure dressings may be a useful aid for stoma closure site wounds.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Estomas Cirúrgicos , Estudos de Casos e Controles , Humanos , Projetos Piloto , Estudos Retrospectivos , Cicatrização
4.
Ann R Coll Surg Engl ; 102(3): e57-e59, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31660767

RESUMO

We report an unusual case of strangulated diaphragmatic hernia secondary to a pericardial ablation, which resulted in necrosis of the incarcerated small bowel. Through a literature search, we have found a limited number of similar cases introducing a case series for this rare but potentially fatal condition.


Assuntos
Técnicas de Ablação/efeitos adversos , Hérnia Diafragmática/etiologia , Obstrução Intestinal/etiologia , Pericárdio/cirurgia , Hérnia Diafragmática/diagnóstico por imagem , Hérnia Diafragmática/cirurgia , Humanos , Obstrução Intestinal/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia
5.
Ann R Coll Surg Engl ; 102(1): e12-e14, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31859525

RESUMO

Malrotation is part of a spectrum of small and large bowel positional and fixational abnormalities caused by the failure of the fetal intestine to complete a 270-degree rotation around the superior mesenteric artery axis. Rarely, it presents in the adult as a cause of acute small bowel obstruction. Chronic symptoms of malrotation in adults are subtle, and include intermittent abdominal pain, nausea and vomiting. We present two cases of malrotation in octogenarian men presenting acutely with small bowel obstruction. Both patients were treated with emergency surgery. In one case the chronic symptoms resolved postoperatively. Malrotation and midgut volvulus should be considered as a rare differential diagnosis for small bowel obstruction in adults. Suspicions should be increased when there is a history of recurrent presentations with similar symptoms.


Assuntos
Obstrução Intestinal/cirurgia , Volvo Intestinal/congênito , Intestino Delgado/cirurgia , Idoso de 80 Anos ou mais , Constipação Intestinal/etiologia , Humanos , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/etiologia , Volvo Intestinal/diagnóstico por imagem , Volvo Intestinal/cirurgia , Intestino Delgado/diagnóstico por imagem , Masculino , Náusea/etiologia , Período Pós-Prandial , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vômito/etiologia
7.
J Nanomed Nanotechnol ; 7(1)2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27081576

RESUMO

We have fabricated protein polymer-gold nanoparticle (P-GNP) nanocomposites that exhibit enhanced binding and delivery properties of the small hydrophobic molecule drug, curcumin, to the model breast cancer cell line, MCF-7. These hybrid biomaterials are constructed via in situ GNP templated-synthesis with genetically engineered histidine tags. The P-GNP nanocomposites exhibit enhanced small molecule loading, sustained release and increased uptake by MCF-7 cells. When compared to the proteins polymers alone, the P-GNPs demonstrate a greater than 7-fold increase in curcumin binding, a nearly 50% slower release profile and more than 2-fold increase in cellular uptake of curcumin. These results suggest that P-GNP nanocomposites serve as promising candidates for drug delivery vehicles.

8.
A A Case Rep ; 3(1): 3-5, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25612265

RESUMO

A 34-year-old parturient developed third-degree atrioventricular block, in the setting of hypotension, after spinal anesthesia for cesarean delivery. The arrhythmia fully resolved with anticholinergic and sympathomimetic drugs. Considering the increasing maternal morbidity and potential risk of maternal cardiac arrest, this critical state is reviewed, and a treatment algorithm is suggested.

9.
Arch Dis Child Fetal Neonatal Ed ; 88(1): F41-5, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12496225

RESUMO

OBJECTIVES: To comprehensively identify preterm infants likely to require blood transfusion and to investigate the effectiveness of recombinant erythropoietin in this high risk subgroup. DESIGN: Double blind randomised controlled trial. SETTING: Neonatal Intensive Care Unit, Middlemore Hospital, Auckland, New Zealand. PATIENTS: Preterm infants < 33 weeks gestation and < 1700 g birth weight meeting specific criteria indicating a high possibility of requiring blood transfusion. INTERVENTIONS: Predictors of blood transfusion were determined by analysis of preterm infants admitted to a neonatal intensive care unit over a two year period. Using the criteria developed, high risk infants entered the study and received erythropoietin or sham treatment until 34 weeks completed gestation. The sample size was calculated to detect a reduction of one blood transfusion per infant (significance level 5%, power 80%). RESULTS: The selection criteria had a positive predictive value for transfusion of 91% and a negative predictive value of 94%. Mean birth weights and gestational ages were similar in the two groups. Absolute reticulocyte counts and haemoglobin values were higher in the group receiving erythropoietin. There was no significant difference in the number of blood transfusions received in the treatment and control groups. However, comparing transfusions given to < 1000 g infants after 30 days of age, there were significantly fewer transfusions in the erythropoietin group (mean (SD) 0.5 (0.7) in those receiving erythropoietin and 1.6 (1.1) in the controls). No adverse effects were noted. CONCLUSIONS: The selection criteria for the study were highly predictive of subsequent transfusion. In the group receiving erythropoietin, a reduction in transfusion requirements was apparent only in the < 1000 g birthweight group after 1 month of age.


Assuntos
Transfusão de Sangue , Eritropoetina/uso terapêutico , Doenças do Prematuro/terapia , Recém-Nascido Prematuro , Contagem de Células Sanguíneas , Doadores de Sangue , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido , Masculino , Proteínas Recombinantes
10.
Ann Bot ; 89(3): 261-72, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12096738

RESUMO

Biomass, net primary productivity, energetics and energy efficiencies were estimated in an age series of Alnus-cardamom plantations in the eastern Himalaya. The impact of stand age (5, 10, 15, 20, 30 and 40 years) on the performance of mixtures of N2-fixing (Alnus nepalensis) and non-N2-fixing (large cardamom) plants was studied. Large cardamom (Amomum subulatum) is the most important perennial cash crop in the region and is cultivated predominantly under Alnus trees. Net primary productivity was lowest (7 t ha(-1) per year) in the 40-year-old stand and was more than three times higher (22 t ha(-1) per year) in the 15-year-old stand. Agronomic yield of large cardamom peaked between 15 and 20 years of age. Cardamom productivity doubled from the 5- to the 15-year-old stand, and then decreased with plantation age to reach a minimum in the 40-year-old stand. Performance of cardamom in association of N2-fixing Alnus remained beneficial until 20 years of age. Annual net energy fixation was highest (444 x 10(6) kJ ha(-1) per year) in the 15-year-old stand, being 1.4 times that of the 5-year-old stand and 2.9-times that of the 40-year-old stand. Inverse relationships of production efficiency, energy conversion efficiency and energy utilized in N2-fixation against stand age, and a positive relationship between production efficiency and energy conversion efficiency suggest that the younger plantations are more productive. The Alnus-cardamom plantation system will be sustainable by adopting a rotational cycle of 15 to 20 years.


Assuntos
Alnus/crescimento & desenvolvimento , Biomassa , Elettaria/crescimento & desenvolvimento , Algoritmos , Alnus/metabolismo , Conservação de Recursos Energéticos/métodos , Ecossistema , Elettaria/metabolismo , Agricultura Florestal/métodos , Índia , Modelos Lineares , Fixação de Nitrogênio/fisiologia , Estruturas Vegetais/crescimento & desenvolvimento , Estruturas Vegetais/metabolismo , Fatores de Tempo
11.
Ann Bot ; 89(3): 273-82, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12096739

RESUMO

Nutrient cycling, nutrient use efficiency and nitrogen fixation in an age series of Alnus-cardamom plantations were studied in the eastern Himalaya. The impact of stand age (5, 10, 15, 20, 30 and 40 years) on the nutrient dynamics of mixtures of N2-fixing (Alnus nepalensis) and non-N2-fixing (large cardamom) plants was assessed. Foliar nutrient concentrations of Alnus decreased with advancing age groups of plantations and showed an inverse relationship with stand age. Annual N fixation increased from the 5-year-old stand (52 kg ha(-1)), peaking in the 15-year-old stand (155 kg ha(-1)) and then decreased with increasing plantation age. Nitrogen and phosphorus uptake was lowest in the 40-year-old stand, and highest in the 15- and 5-year-old stand, respectively. Nutrient storage in understorey cardamom was very high: up to 31 % N and 59 % P of the stand total in the 15-year-old stand. Nutrient use efficiency was higher (with faster turnover times) in younger stands and decreased (with slower turnover times) in older plantations. Nitrogen retranslocation showed a strong positive relationship with stand age, while that of P was inversely related to stand age. Nutrient standing stock, uptake and return were also highest in the 15-year-old stand. Nitrogen and P cycling in Alnus-cardamom plantations was functionally balanced. Nutrient cycling and dynamics indicated that Alnus-cardamom plantations performed sustainably up to 15-20 years. The management practice should be altered to incorporate replantation after this age.


Assuntos
Alnus/metabolismo , Elettaria/metabolismo , Fixação de Nitrogênio/fisiologia , Nitrogênio/metabolismo , Fósforo/metabolismo , Algoritmos , Alnus/química , Alnus/crescimento & desenvolvimento , Transporte Biológico , Biomassa , Conservação dos Recursos Naturais/métodos , Ecossistema , Elettaria/química , Elettaria/crescimento & desenvolvimento , Agricultura Florestal/métodos , Índia , Modelos Lineares , Estruturas Vegetais/química , Estruturas Vegetais/crescimento & desenvolvimento , Estruturas Vegetais/metabolismo , Fatores de Tempo
12.
J Endourol ; 15(8): 789-91, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11724115

RESUMO

PURPOSE: To assess retrospectively the safety and efficacy of the supracostal approach in percutaneous nephrolithotomy (PCNL). PATIENTS AND METHODS: Among 862 patients who underwent PCNL between April 1986 and December 1999, supracostal puncture was performed in 102. Their stones were either solitary (66.5%), multiple (15.7%), or staghorn (19.6%). Upper ureteral calculi were the commonest indication (32.4%). The interspace between the 11th and 12th ribs was used in all cases. After tract dilatation with telescopic metal dilators, pneumatic or ultrasound lithotripsy was used for fragmentation. RESULTS: Complete clearance was achieved in 79.5%. Ten patients (9.8%) had pleural violation in the form of hydrothorax, pneumothorax, or hydropneumothorax. All of these patients were managed successfully by intercostal chest tube drainage. CONCLUSION: Supracostal puncture in a safe and effective approach with acceptable morbidity in selected cases of staghorn, upper ureteral, and upper caliceal calculi.


Assuntos
Nefrostomia Percutânea/métodos , Cálculos Ureterais/cirurgia , Adulto , Idoso , Tubos Torácicos , Drenagem/métodos , Feminino , Humanos , Hidropneumotórax/etiologia , Hidropneumotórax/terapia , Hidrotórax/etiologia , Hidrotórax/terapia , Masculino , Pessoa de Meia-Idade , Nefrostomia Percutânea/efeitos adversos , Pneumotórax/etiologia , Pneumotórax/terapia , Estudos Retrospectivos , Costelas
13.
J Environ Manage ; 61(2): 123-35, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11381770

RESUMO

The Khanikhola watershed in Sikkim is agrarian with about 50% area under rain-fed agriculture representing the conditions of the middle mountains all over the Himalaya. The study was conducted to assess overland flow, soil loss and subsequent nutrient losses from different land uses in the watershed, and identify biotechnological inputs for management of mountain farming systems. Overland flow, soil and nutrient losses were very high from open agricultural (cropped) fields compared to other land uses, and more than 72% of nutrient losses were attributable to agriculture land use. Forests and large cardamom agroforestry conserved more soil compared to other land uses. Interventions, like cultivation of broom grass upon terrace risers, N2-fixing Albizia trees for maintenance of soil fertility and plantation of horticulture trees, have reduced the soil loss (by 22%). Soil and water conservation values (> 80%) of both large cardamom and broom grass were higher compared to other crops. Use of N2-fixing Albizia tree in large cardamom agroforestry and croplands contributed to soil fertility, and increased productivity and yield. Bio-composting of farm resources ensured increase in nutrient availability specially phosphorus in cropped areas. Agricultural practices in mountain areas should be strengthened with more agroforestry components, and cash crops like large cardamom and broom grass in agroforestry provide high economic return and are hydroecologically sustainable.


Assuntos
Agricultura , Conservação dos Recursos Naturais , Ecossistema , Humanos , Índia , Solo , Árvores , Água
14.
J Neurosci ; 16(24): 7821-31, 1996 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8987810

RESUMO

The STEP family of protein tyrosine phosphatases is highly enriched within the CNS. Members of this family are alternatively spliced to produce both transmembrane and cytosolic variants. This manuscript describes the distinctive intracellular distribution and enzymatic activity of the membrane-associated isoform STEP61. Transfection experiments in fibroblasts, as well as subcellular fractionations, sucrose density gradients, immunocytochemical labeling, and electron microscopy in brain tissue, show that STEP61 is an intrinsic membrane protein of striatal neurons and is associated with the endoplasmic reticulum. In addition, structural analysis of the novel N-terminal region of STEP61 reveals several motifs not present in the cytosolic variant STEP46. These include two putative transmembrane domains, two sequences rich in Pro, Glu, Asp, Ser, and Thr (PEST sequences), and two polyproline-rich domains. Like STEP46, STEP61 is enriched in the brain, but the recombinant protein has less enzymatic activity than STEP46. Because STEP46 is contained in its entirety within STEP61 and differs only in the extended N terminus of STEP61, this amino acid sequence is responsible for the association of STEP61 with membrane compartments and may also regulate its enzymatic activity.


Assuntos
Encéfalo/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Sequência de Aminoácidos , Animais , Northern Blotting , Encéfalo/ultraestrutura , Células CHO/metabolismo , Cricetinae , Imuno-Histoquímica , Microscopia Eletrônica , Dados de Sequência Molecular , Proteínas Tirosina Fosfatases/genética , Ratos , Distribuição Tecidual , Transfecção
15.
Brain Res Mol Brain Res ; 32(1): 87-93, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7494467

RESUMO

A brain-enriched protein tyrosine phosphatase termed STEP46 (striatal enriched phosphatase) was previously isolated and characterized. Immunological studies with a STEP monoclonal antibody recognized several STEP-immunoreactive proteins, and suggested that additional STEP-related polypeptides existed. This study reports the isolation of two alternatively spliced transcripts of the STEP gene. One of these, STEP20 (with a predicted molecular mass of 20 kDa) was further characterized and found to lack the conserved tyrosine phosphatase domain. Northern analysis detected a 2.8 kb STEP20 message in mouse brain. The second alternatively spliced transcript, STEP61, has a 5'-extended open reading frame that encodes a protein with a predicted molecular mass of 61 kDa and contains a single tyrosine phosphatase domain. The exon-intron organization responsible for the novel STEP20 and STEP61 sequences was determined in the mouse STEP genomic DNA. We propose that the original STEP46, along with STEP20 and STEP61, are members of a brain-enriched subfamily of protein tyrosine phosphatases, and that STEP isoforms may have distinct functions within the central nervous system.


Assuntos
Processamento Alternativo , DNA Complementar/isolamento & purificação , Fases de Leitura Aberta , Estrutura Terciária de Proteína , Proteínas Tirosina Fosfatases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Códon , Éxons , Biblioteca Genômica , Íntrons , Camundongos , Dados de Sequência Molecular , Proteínas Tirosina Fosfatases não Receptoras , Homologia de Sequência de Aminoácidos
16.
J Biol Chem ; 270(1): 49-53, 1995 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-7814416

RESUMO

A new protein tyrosine phosphatase (PC12-PTP1) was identified in nerve growth factor (NGF)-treated PC12 cells. The mRNA level of PC12-PTP1 is increased 9-fold over the initial 8 h of NGF treatment and then decreases dramatically after 24 h of treatment. In rat brain, three transcripts corresponding to 1.5, 2.6, and 3.0 kilobases (kb) in size are detected by Northern blot analysis. Although the 1.5- and 2.6-kb transcripts are present in brain and other tissues, the 3-kb transcript is exclusively expressed in brain and the expression of this transcript alone increases following NGF treatment. PC12-PTP1 is a non-receptor protein tyrosine phosphatase (PTP) with a 50% sequence homology in the phosphatase domain with several other non-receptor PTPs. PC12-PTP1 fusion protein exhibits tyrosine phosphatase activity, and in vitro translation of the PC12-PTP1 transcript produces a major protein of 39 kDa. The data presented suggest that NGF regulates the expression of PC12-PTP1 during periods of neuronal growth and differentiation.


Assuntos
Fatores de Crescimento Neural/farmacologia , Proteínas do Tecido Nervoso/biossíntese , Neurônios/enzimologia , Proteínas Tirosina Fosfatases/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA , Indução Enzimática , Peptídeos e Proteínas de Sinalização Intracelular , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/genética , Células PC12 , Proteínas Tirosina Fosfatases/genética , Ratos , Proteínas Tirosina Fosfatases Classe 7 Semelhantes a Receptores , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Homologia de Sequência de Aminoácidos
18.
Opt Lett ; 20(9): 1005, 1995 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19859405
19.
Opt Lett ; 20(20): 2081-3, 1995 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19862257

RESUMO

We propose a new semianalytical method using variational analysis for developing an equivalent three-layer model of a multiple-quantum-well waveguide. Waveguiding properties such as effective index and field distribution of this equivalent waveguide are compared with those of previously reported equivalents and with the results obtained from the exact multilayer analysis of the multiple-quantum-well waveguide. The waveguiding properties are accurately predicted by this method, and the computational effort is significantly reduced.

20.
Ann Bot ; 75(1): 5-11, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21247907

RESUMO

A study on five naturally growing epiphytic orchids viz., Bulbophyllum affine Lindl., Coelogyne ochracea Lindl., Otochilus porrecta Lindl., Cirrhopetalum cornutum Lindl. and C. cornutum (var.) was carried out in the subtropical belt of Sikkim Himalaya. Stemflow leachates formed the main source of ammonium-N and nitrate-N for uptake by these orchids. Phosphorus concentration in the tissues of these orchids was high. Phosphate-P from stemflow does not seem to be a regular source of phosphorus for these orchids. Absorption/desorption results indicate that organic-N from stemflow leachates is not utilized by these orchids.

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