551 resultados para Ballasts (lamp)


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Tank cultivation of marine macroalgae involves air-agitation of the algal biomass and intermittent light conditions, i.e. periodic, short light exposure of the thalli in the range of 10 s at the water surface followed by plunging to low light or darkness at the tank bottom and recirculation back to the surface in the range of 1-2 min. Open questions relate to effects of surface irradiance on growth rate and yield in such tumble cultures and the possibility of chronic photoinhibition in full sunlight. A specially constructed shallow-depth tank combined with a dark tank allowed fast circulation times of approximately 5 s, at a density of 4.2 kg fresh weight (FW) m(-2) s(-1). Growth rate and yield of the red alga Palmaria palmata increased over a wide range of irradiances, with no signs of chronic photoinhibition, up to a growth-saturating irradiance of approximately 1600 mumol m(-2) s(-1) in yellowish light supplied by a sodium high pressure lamp at 16 h light per day. Maximum growth rate ranged at 12% FW d(-1), and maximum yield at 609 g FW m(-2) d(-1). This shows that high growth rates of individual thalli may be reached in a dense tumble culture, if high surface irradiances and short circulation times are supplied. Another aspect of intermittent light relates to possible changes of basic growth kinetics, as compared to continuous light. For this purpose on-line measurements of growth rate were performed with a daily light reduction by 50% in light-dark cycles of 1, 2 or 3 min duration during the daily light period. Growth rates at 10degreesC and 50 mumol photon m(-2) s- 1 dropped in all three intermittent light regimes during both the main light and dark periods and reached with all three periodicities approximately 50% of the control, with no apparent changes in basic growth kinetics, as compared to continuous light.

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对虾病害在世界范围内肆虐,给水产养殖和沿海农村经济造成了重大损失。在水产养殖的实践中快速检测水产动物的病害并及时采取隔离等措施对于控制病害尤为重要,其中关键的环节就是快速检测出病害,并在对虾免疫机制上寻找对虾疾病防治的有效方法。研究表明当对虾等甲壳动物受到外界病原刺激时,极微量的微生物多糖就可以激活proPO系统。激活过程中涉及和产生一系列活性物质,如黑色素、酚氧化酶原激活因子(PPA)、模式识别蛋白(BGBP、PGBP、LGBP、LBP)及其膜上受体和A2巨球蛋白等,它们可通过多种方式参与防御反应,包括提供调理素,促进血细胞吞噬作用,形成结节或包囊以及介导凝集和凝固,产生杀菌物质并且黑色素化。黑色素常常在节肢动物的体表形成黑色斑点,形成的色素沉着对机体起到保护作用。所以,酚氧化酶原激活的级联反应是节肢动物免疫的关键因素。本论文研究开发了以环等温介导技术(LAMP)为基础的检测对虾白斑病毒(WSSV)和鳗弧菌(V. anguillarum)的快速检测方法。并从对虾对病害的免疫机制为切入点,从中国明对虾体内克隆了酚氧化酶原(PrpPO)和丝氨酸蛋白酶FcSP3这两个免疫系统中重要的基因,分析了它们的分子结构特征,组织分布及应答鳗弧菌病原刺激的表达变化模式。 建立的对虾常见病害对虾白班病毒(WSSV)和鳗弧菌(V. anguillarum)的LAMP检测方法,经过实验比对和Blast检索,发现本研究中使用的引物,比已经报导的LAMP方法或者PCR方法具有更宽的检测范围(更低的假阴性)。检测WSSV的LAMP方法使用病毒的VP28基因设计引物,而鳗弧菌的检测方法使用empA基因设计引物。在方法中,首次提出加入UNG酶和dUTP的措施来预防污染,在实际检测中非常有效。LAMP方法与PCR检测方法的灵敏性比较也进行了研究,二者灵敏性相当。 依据中国明对虾血液cDNA文库提供的部分片段信息,结合SMART-RACE技术,克隆了酚氧化酶原(PrpPO)基因,通过序列比对分析发现,PrpPO基因cDNA全长为3040 bp,其中开放阅读框2061 bp,编码686个氨基酸,其中推测的信号肽为12个氨基酸。推测的序列与斑节对虾(P. monodon)同源性为93%,与短钩对虾(P. semisulcatus.)同源性为92%。real time RT-PCR实验结果表明, ProPO在血细胞中的相对表达量最高,肝胰脏中表达量最低。弧菌刺激实验中注射弧菌,刺激了血细胞和淋巴器官中的ProPO mRNA显著增加,说明在血细胞和淋巴器官中存在快速反应的ProPO通路。而ProPO mRNA量在淋巴器官中在时间上早于血液中升至最高,说明该动物在在病原刚开始入侵的时候先有淋巴器官发挥主要的免疫作用,随着时间推移血细胞便变成主要的免疫器官。 根据中国明对虾肝胰脏cDNA文库提供EST信息,经过SMART-RACE克隆了一个丝氨酸蛋白酶FcSP3基因,通过序列比对分析发现,该丝氨酸蛋白酶基因cDNA全长为1622 bp,其中开放阅读框1431 bp,编码477个氨基酸,其中推测的信号肽为22个氨基酸。推测的序列与疟蚊的丝氨酸蛋白酶(A. gambiae)同源性为33%,与丽蝇蛹集金小蜂的酚氧化酶原激活因子(N. vitripennis)同源性为32%,与东北大黑鳃金龟的酚氧化酶原激活因子(H. diomphalia)同源性为34%。淋巴器官中PPAⅡ表达量约为血液中表达量的47560倍,肝胰脏中的FCSP3表达量为血细胞表达量的6226倍。鳗弧菌注射对虾后,淋巴器官中刺激组和对照组FcSP3的mRNA量在刺激后6小时显著降低,但是刺激组的表达量明显高于对照组。刺激组的血细胞与肝胰脏中FcSP3 mRNA的相对表达量增高。而病原刺激后的血液与肝胰脏中的FcSP3 mRNA的增长趋势也在时间上先与ProPO mRNA。这说明FcSP3对ProPO有正调控的作用,但这个调控有一个时间差,并且在不同组织中有不同的调控效率。

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自转基因作物问世以来,转基因产品的安全性问题一直是人们关注的焦点。本文根据GenBank中登录的转基因大豆完整外源DNA序列设计了几对引物,对转基因大豆进行了巢式PCR检测。结果表明,巢式PCR可以扩增10-10g/μl浓度的DNA溶液,检测灵敏度高达0.01%。该巢式PCR技术具有高度特异性、灵敏度和很好的重复性。用巢式PCR对部分市售的水产饲料和豆制食品进行检测,90.6%的水产饲料和46.5%的食品能检测出外源基因片段,表明转基因大豆广泛存在于水产饲料和我们的日常食品中,为食品安全分析和管理提供了方法和依据。环介导的等温扩增技术(LAMP)依赖于能够识别靶序列上6个特异区域的引物和一种具有链置换特性的DNA聚合酶,在等温条件下可高效、快速、高特异地扩增靶序列。本研究建立了转基因大豆的LAMP扩增技术,针对豆制品以及饲料的转基因LAMP检测技术正在研究和开发中。 利用转基因和非转基因豆粕制作的饲料,喂养吉富罗非鱼,分别于4周、7周取样,对其体重和血液指标进行了检测。实验显示,投喂转基因饲料7周以后,增重率和血清指标,转基因组与非转基因饲料组相比没有显著差异。全血指标中白细胞数目、大血小板比率、平均血小板体积和血小板体积分布宽度4项指标显著高于非转基因饲料组,而且差异达到极显著水平。由以上结果可见,转基因大豆与非转基因大豆相比,对罗非鱼的一些生理过程造成了一定的影响,但是并未对其生长造成可见的影响。分别于投喂1h、4h和8h以后取罗非鱼胃内容物、肠道内容物和粪便,并分别于4周、7周和继续饥饿2周后,取罗非鱼不同组织,提取DNA,用巢式PCR法检测转基因大豆中的外源基因在各种组织中的分布,结果显示在胃内容物、肠内容物、粪便、心脏、肝脏、胃、肠、卵巢、精巢、脑、鳃丝、脾脏、胆囊、肌肉等不同部位的DNA中都能检测到外源基因的存在,说明转基因大豆中的外源DNA并不能被罗非鱼的消化道完全降解,其DNA片段可能通过消化吸收转移到鱼体的各种组织。在投喂转基因饲料7周以后以及停止投喂饥饿2周以后分离水体中的微生物,提取其DNA,进行转基因检测。结果显示在所分离纯化的各种微生物中都没有检测到转基因大豆中外源基因35S-EPSPS的存在。

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Shrimps Litopenaeus vannamei with initial body weight of 2.108 +/- 0.036 g were sampled for specific growth rates (SGR) and body color measurements for 50 days under different light sources (incandescent lamp, IL; cool-white fluorescent lamp, FL; metal halide lamp, MHL; and control without lamp) and different illumination methods (illumination only in day, IOD, and illumination day and night, IDN). Body color of L. vannamei was measured according to the free astaxanthin concentration (FAC) of shrimp. The SGR, food intake (FI), feed conversion efficiency (FCE) and FAC of shrimps showed significant differences among the experimental treatment groups (P < 0.05). Maximum and minimum SGR occurred under IOD by MHL and IDN by FL, respectively (difference 56.34%). The FI of shrimp for the control group did not rank lowest among treatments, confirming that shrimp primarily use scent, not vision, to search for food. FI and FCE of shrimps were both the lowest among treatment groups under IDN by FL and growth was slow, thus FL is not a preferred light source for shrimp culture. Under IOD by MHL, shrimps had the highest FCE and the third highest FI among treatment groups ensuring rapid growth. FAC of shrimp were about 3.31 +/- 0.20 mg/kg. When under IOD by MHL and IDN by FL, FAC was significantly higher than the other treatments (P < 0.05). To summarize, when illuminated by MHL, L. vannamei had not only vivid body color due to high astaxanthin concentration but also rapid growth. Therefore, MHL is an appropriate indoor light source for shrimp super-intensive culture. SGR of shrimp was in significantly negative correlation to FAC of shrimp (P < 0.05). Thus, when FAC increased, SGR did not always follow, suggesting that the purpose of astaxanthin accumulation was not for growth promotion but for protection against intense light. (c) 2005 Elsevier B.V. All rights reserved.

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Using the LAMP method, a highly specific and sensitive detection system for genetically modified soybean (Roundup Ready) was designed. In this detection system, a set of four primers was designed by targeting the exogenous 35S epsps gene. Target DNA was amplified and visualized on agarose gel within 45 min under isothermal conditions at 65 degrees C. Without gel electrophoresis, the LAMP amplicon was visualized directly in the reaction tube by the addition of SYBR Green I for naked-eye inspection. The detection sensitivity of LAMP was 10-fold higher than the nested PCR established in our laboratory. Moreover, the LAMP method was much quicker, taking only 70 min, as compared with 300 min for nested PCR to complete the analysis of the GM soybean. Compared with traditional PCR approaches, the LAMP procedure is faster and more sensitive, and there is no need for a special PCR machine or electrophoresis equipment. Hence, this method can be a very useful tool for GMO detection and is particularly convenient for fast screening.

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为了避免人眼对产品外观质量检测时,人眼视觉疲劳所产生的产品错检、漏检,提出了基于机器视觉的烟支条盒包装质量检测系统的设计。该系统由光源、相机、图像采集卡和工业控制计算机组成视觉系统处理单元,应用定位配准、边缘检测和斑点分析等图像处理算法完成对产品缺陷的检测。该视觉检测系统已经在烟厂得到了实际应用,对今后开发类似的基于机器视觉的产品外观质量检测系统具有一定的参考价值和指导意义。

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Wydział Fizyki: Zakład Optyki

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VCP (VCP/p97) is a ubiquitously expressed member of the AAA(+)-ATPase family of chaperone-like proteins that regulates numerous cellular processes including chromatin decondensation, homotypic membrane fusion and ubiquitin-dependent protein degradation by the proteasome. Mutations in VCP cause a multisystem degenerative disease consisting of inclusion body myopathy, Paget disease of bone, and frontotemporal dementia (IBMPFD). Here we show that VCP is essential for autophagosome maturation. We generated cells stably expressing dual-tagged LC3 (mCherry-EGFP-LC3) which permit monitoring of autophagosome maturation. We determined that VCP deficiency by RNAi-mediated knockdown or overexpression of dominant-negative VCP results in significant accumulation of immature autophagic vesicles, some of which are abnormally large, acidified and exhibit cathepsin B activity. Furthermore, expression of disease-associated VCP mutants (R155H and A232E) also causes this autophagy defect. VCP was found to be essential to autophagosome maturation under basal conditions and in cells challenged by proteasome inhibition, but not in cells challenged by starvation, suggesting that VCP might be selectively required for autophagic degradation of ubiquitinated substrates. Indeed, a high percentage of the accumulated autophagic vesicles contain ubiquitin-positive contents, a feature that is not observed in autophagic vesicles that accumulate following starvation or treatment with Bafilomycin A. Finally, we show accumulation of numerous, large LAMP-1 and LAMP-2-positive vacuoles and accumulation of LC3-II in myoblasts derived from patients with IBMPFD. We conclude that VCP is essential for maturation of ubiquitin-containing autophagosomes and that defect in this function may contribute to IBMPFD pathogenesis.

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PURPOSE: To report a rare case of atypical fibroxanthoma (AFX) of the bulbar conjunctiva, and to compare it with previously published cases of conjunctival AFX. METHODS: A 37-year-old woman developed a growth on the bulbar conjunctiva of her left eye that increased in size and redness over 4 months and was associated with blurry vision in the left eye, occasional diplopia, irritation of the eye, and increasing tearing. The mass was surgically excised. RESULTS: Slit-lamp examination disclosed a highly vascularized conjunctival lesion with intact lustrous epithelium and a raised nodular edge encroaching on the nasal corneal limbus of the left eye. Pathological examination and immunohistochemistry were diagnostic of AFX. CONCLUSIONS: AFX of the conjunctiva is rare, with this being only the fifth example of this neoplasm reported at this site. Complete surgical excision is the most appropriate treatment option.

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OBJECTIVE: The aim of this study was to investigate how the release of fluoride from two compomers and a fluoridated composite resin was affected by exposure to KF solution. MATERIAL AND METHODS: Two compomers (Dyract AP and Compoglass F) and one fluoridated composite (Wave) were prepared as discs (6 mm diameter and 2 mm thick), curing with a standard dental lamp. They were then stored in either water or 0.5% KF for 1 week, followed by placement in water for periods of 1 week up to 5 weeks total. Fluoride was determined with and without TISAB (to allow complexed and decomplexed fluoride to be determined), and other ion release (Na, Ca, Al, Si, P) was determined by ICP-OES. RESULTS: Specimens were found not to take up fluoride from 100 ppm KF solution in 24 h, but to release additional fluoride when stored for up to five weeks. Compomers released more fluoride cumulatively following exposure to KF solution (p<0.001), all of which was decomplexed, though initial (1 week) values were not statistically significant for Dyract AP. Other ions showed no variations in release over 1 week, regardless of whether the specimens were exposed to KF. Unlike the compomers, Wave showed no change in fluoride release as a result of exposure to KF. CONCLUSIONS: Compomers are affected by KF solution, and release more fluoride (but not other ions) after exposure than if stored in water.

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Macromolecular therapeutics and nano-sized drug delivery systems often require localisation to specific intracellular compartments. In particular, efficient endosomal escape, retrograde trafficking, or late endocytic/lysosomal activation are often prerequisites for pharmacological activity. The aim of this study was to define a fluorescence microscopy technique able to confirm the localisation of water-soluble polymeric carriers to late endocytic intracellular compartments. Three polymeric carriers of different molecular weight and character were studied: dextrin (Mw~50,000 g/mol), a N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer (Mw approximately 35,000 g/mol) and polyethylene glycol (PEG) (Mw 5000 g/mol). They were labelled with Oregon Green (OG) (0.3-3 wt.%; <3% free OG in respect of total). A panel of relevant target cells were used: THP-1, ARPE-19, and MCF-7 cells, and primary bovine chondrocytes (currently being used to evaluate novel polymer therapeutics) as well as NRK and Vero cells as reference controls. Specific intracellular compartments were marked using either endocytosed physiological standards, Marine Blue (MB) or Texas-red (TxR)-Wheat germ agglutinin (WGA), TxR-Bovine Serum Albumin (BSA), TxR-dextran, ricin holotoxin, C6-7-nitro-2,1,3-benzoxadiazol-4-yl (NBD)-labelled ceramide and TxR-shiga toxin B chain, or post-fixation immuno-staining for early endosomal antigen 1 (EEA1), lysosomal-associated membrane proteins (LAMP-1, Lgp-120 or CD63) or the Golgi marker GM130. Co-localisation with polymer-OG conjugates confirmed transfer to discreet, late endocytic (including lysosomal) compartments in all cells types. The technique described here is a particularly powerful tool as it circumvents fixation artefacts ensuring the retention of water-soluble polymers within the vesicles they occupy.

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Many previous studies into internal temperature gradients within stone have assumed smooth, exponential increases and decreases in sub-surface temperatures in response, for example, to diurnal patterns of heating and cooling and these have been used to explain phenomena such as large-scale contour scaling. This high-resolution experimental study, in which a porous limestone block was subjected to alternate surface heating and cooling using an infrared lamp, demonstrates that internal temperature gradients in response to short-term environmental cycles (measured in minutes) can in fact be complex and inconsistent. Results confirm the significance of very steep temperature/stress gradients within the outer 10 mm or less of exposed stone. Below this the data indicate complex patterns of temperature reversals, the amplitudes of which are attenuated with depth and which are influenced in their intensity and location by variations in the relative duration of heating and cooling phases. It is suggested that the reversals might represent ‘interference patterns’ between incoming and outgoing thermal waves, but whatever their origin they are potentially important because they occur within the zone in which many stone decay processes, especially salt weathering, operate. These processes invariably respond to temperature and moisture fluctuations, and short-term interruptions to insolation could, for example, trigger these fluctuations on numerous occasions over a day. In particular, the reversals occur at a scale that is commensurate with decay by multiple flaking and could indicate an underlying control on this previously little-researched pattern of weathering. In the context of this publication, however, the main lesson to be learned from this study is that differing scales of behaviour require different scales of enquiry.

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Objective: To describe the ocular phenotype in patients with ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome (MIM#604292) and to determine the pathogenic basis of visual morbidity. Design: Retrospective case series. Participants: Nineteen families (23 patients) affected by EEC syndrome from the United Kingdom, Ireland, and Italy. Methods: General medical examination to fulfill the diagnostic criteria for EEC syndrome and determine the phenotypic severity. Mutational analysis of p63 was performed by polymerase chain reaction-based bidirectional Sanger sequencing. All patients with EEC syndrome underwent a complete ophthalmic examination and ocular surface assessment. Limbal stem cell deficiency (LSCD) was diagnosed clinically on the basis of corneal conjunctivalization and anatomy of the limbal palisades of Vogt. Impression cytology using immunofluorescent antibodies was performed in 1 individual. Histologic and immunohistochemical analyses were performed on a corneal button and corneal pannus from 2 EEC patients. Main Outcome Measures: The EEC syndrome phenotypic severity (EEC score), best-corrected Snellen visual acuity (decimal fraction), slit-lamp biomicroscopy, tear function index, tear breakup time, LSCD, p63 DNA sequence variants, impression cytology, and corneal histopathology. Results: Eleven heterozygous missense mutations in the DNA binding domain of p63 were identified in all patients with EEC syndrome. All patients had ocular involvement and the commonest was an anomaly of the meibomian glands and lacrimal drainage system defects. The major cause of visual morbidity was progressive LSCD, which was detected in 61% (14/23). Limbal stem cell deficiency was related to advancing age and caused a progressive keratopathy, resulting in a dense vascularized corneal pannus, and eventually leading to visual impairment. Histologic analysis and impression cytology confirmed LSCD. Conclusions: Heterozygous p63 mutations cause the EEC syndrome and result in visual impairment owing to progressive LSCD. There was no relationship of limbal stem cell failure with the severity of EEC syndrome, as classified by the EEC score, or the underlying molecular defect in p63. Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article. © 2012 American Academy of Ophthalmology.

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Indicator inks, previously shown to be capable of rapidly assessing photocatalytic activity via a novel photo-reductive mechanism, were simply applied via an aerosol spray onto commercially available pieces of Activ (TM) self-cleaning glass. Ink layers could be applied with high evenness of spread, with as little deviation as 5% upon UV-visible spectroscopic assessment of 25 equally distributed positions over a 10 cm x 10 cm glass cut. The inks were comprised of either a resazurin (Rz) or dichloroindophenol (DCIP) redox dye with a glycerol sacrificial electron donor in an aqueous hydroxyethyl cellulose (HEC) polymer media. The photo-reduction reaction under UVA light of a single spot was monitored by UV-vis spectroscopy and digital images attained from a flat-bed scanner in tandem for both inks. The photo-reduction of Rz ink underwent a two-step kinetic process, whereby the blue redox dye was initially reduced to a pink intermediate resorufin (Rf) and subsequently reduced to a bleached form of the dye. In contrast, a simple one-step kinetic process was observed for the reduction of the light blue redox dye DCIP to its bleached intermediates. Changes in red-green-blue colour extracted from digital images of the inks were inversely proportional to the changes seen at corresponding wavelengths via UV-visible absorption spectroscopy and wholly indicative of the reaction kinetics. The photocatalytic activity areas of cuts of Activ (TM) glass, 10 cm x 10 cm in size, were assessed using both Rz and DCIP indicator inks evenly sprayed over the films: firstly using UVA lamp light to activate the underlying Activ (TM) film (1.75 mW cm(-2)) and secondly under solar conditions (2.06 +/- 0.14 mW cm(-2)). The photo-reduction reactions were monitored solely by flat-bed digital scanning. Red-green-blue values of a generated 14 x 14 grid (196 positions) that covered the entire area of each film image were extracted using a Custom-built program entitled RGB Extractor(C). A homogenous degradation over the 196 positions analysed for both Rz (Red colour deviation = 19% UVA, 8% Solar: Green colour deviation = 17% UVA, 12% Solar) and DCIP (Red colour deviation = 22% UVA, 16% Solar) inks was seen in both UVA and solar experiments, demonstrating the consistency of the self-cleaning titania layer on Activ (TM). The method presented provides a good solution for the high-throughput photocatalytic screening of a number of homogenous photocatalytically active materials simultaneously or numerous positions on a single film; both useful in assessing the homogeneity of a film or determining the best combination of reaction components to produce the optimum performance photocatalytic film. (C) 2010 Elsevier B.V. All rights reserved.

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Loop-mediated isothermal amplification (LAMP) is an innovative technique that allows the rapid detection of target nucleic acid sequences under isothermal conditions without the need for complex instrumentation. The development, optimization, and clinical validation of a LAMP assay targeting the ctrA gene for the rapid detection of capsular Neisseria meningitidis were described. Highly specific detection of capsular N. meningitidis type strains and clinical isolates was demonstrated, with no cross-reactivity with other Neisseria spp. or with a comprehensive panel of other common human pathogens. The lower limit of detection was 6 ctrA gene copies detectable in 48 min, with positive reactions readily identifiable visually via a simple color change. Higher copy numbers could be detected in as little as 16 min. When applied to a total of 394 clinical specimens, the LAMP assay in comparison to a conventional TaqMan® based real-time polymerase chain reaction system demonstrated a sensitivity of 100% and a specificity of 98.9% with a ? coefficient of 0.942. The LAMP method represents a rapid, sensitive, and highly specific technique for the detection of N. meningitidis and has the potential to be used as a point-of-care molecular test and in resource-poor settings.