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1.
Toxicon ; 165: 1-12, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31004611

RESUMO

Biological control of cyanobacteria is a viable means of controlling nuisance bloom occurrences; however the majority of studies done are against Microcystis sp., with a commonly lytic effect caused. Filamentous cyanobacteria such as Oscillatoria are not as extensively studied in this area of biological control and are often part of Microcystis dominated blooms. This study employed heterotrophic bacterial isolates selected from bloom waters that indicated potential predatory behaviour against both filamentous and colonial cyanobacterial isolates. In comparison to a known Bacillus isolate, which is often reported among bacterial control agents, three other bacteria isolates were tested as control agents against non-axenic Oscillatoria and Microcystis cyanobacterial cultures. Assessments of cyanobacterial cell responses to the bacteria were conducted through water chemistry, chlorophyll a, alkaline phosphatase activity, microscopy and cyanotoxin measurements. The changes in these parameters were compared to untreated cyanobacterial cultures where no bacteria were added. The study found that at ratios of bacteria half that of Microcystis, minimal changes in chlorophyll a were observed, whilst Oscillatoria showed a decreased chlorophyll a more in the presence of isolates 1 and 3w. The assessment of alkaline phosphatase activity showed decreased activity in both cyanobacterial isolates exposed to the bacteria, relative to the untreated control sample. Microscopy analysis through fluorescence indicated that the attachment of the bacteria to the surface of the cyanobacteria hampered with the fluorescence and scanning electron microscopy indicated that the cells were damaged by the addition of the bacterial isolates. Cyanotoxin detection through the ELISA kit testing indicated that there was toxin reduction in samples treated with the bacterial isolates, with the highest reduction being close to 60% in the case of Microcystis sp. treated with isolate 3w. Similar reductions were noted in the filamentous cyanobacterium Oscillatoria, in the presence of isolate 1.


Assuntos
Bactérias/metabolismo , Proliferação Nociva de Algas , Microcystis/fisiologia , Oscillatoria/fisiologia , Clorofila A/metabolismo , Processos Heterotróficos , Lagos/microbiologia , Microcystis/crescimento & desenvolvimento , Microcystis/isolamento & purificação , Oscillatoria/crescimento & desenvolvimento , Oscillatoria/isolamento & purificação , Toxinas Biológicas/metabolismo
2.
Appl Microbiol Biotechnol ; 102(23): 9911-9923, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30267126

RESUMO

Biological control of cyanobacteria is a well-researched area with a central focus on laboratory-scale studies. Numerous reports have been made on algicidal isolates, with bacteria as a major component of the antagonists. The research in this review draws a brief summary of what is currently known in the area of freshwater cyanobacteria being inhibited by bacterial isolates. Proteobacteria, Bacteroidetes and Firmicutes are among the most commonly reported phyla of bacteria associated with or employed in this research area. However, there are limited reports of upscaling these control measures beyond the laboratory scale. Lytic control agents are the most commonly reported in the literature with subsequent cyanotoxin release. From a water quality perspective, this is not feasible. Based on the available literature, temperature, pH and nutrient changes have been explored in this short review as possible contributors to less optimal bacterial performance. Moreover, the investigation into optimising some of these parameters may lead to increased bacterial performance and, therefore, viability for upscaling this biological control. Through the compilation of current research, this review offers insight to live predator-prey cell interactions between cyanobacteria and algicidal bacteria.


Assuntos
Agentes de Controle Biológico , Cianobactérias/crescimento & desenvolvimento , Água Doce/microbiologia , Toxinas Bacterianas/química , Bacteroidetes/fisiologia , Estudos de Viabilidade , Firmicutes/fisiologia , Concentração de Íons de Hidrogênio , Proteobactérias/fisiologia , Temperatura , Microbiologia da Água , Qualidade da Água
3.
Harmful Algae ; 60: 11-26, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28073554

RESUMO

Cyanobacterial blooms are a current cause for concern globally, with vital water sources experiencing frequent and increasingly toxic blooms in the past decade. These increases are resultant of both anthropogenic and natural factors, with climate change being the central concern. Of the more affected parts of the world, Africa has been considered particularly vulnerable due to its historical predisposition and lag in social economic development. This review collectively assesses the available information on cyanobacterial blooms in Africa as well as any visible trends associated with reported occurrences over the last decade. Of the 54 countries in Africa, only 21 have notable research information in the area of cyanobacterial blooms within the last decade, although there is substantial reason to attribute these blooms as some of the major water quality threats in Africa collectively. The collected information suggests that civil wars, disease outbreaks and inadequate infrastructure are at the core of Africa's delayed advancement. This is even more so in the area of cyanobacteria related research, with 11 out of 21 countries having recorded toxicity and physicochemical parameters related to cyanobacterial blooms. Compared to the rest of the continent, peripheral countries are at the forefront of research related to cyanobacteria, with countries such as Angola having sufficient rainfall, but poor water quality with limited information on bloom occurrences. An assessment of the reported blooms found nitrogen concentrations to be higher in the water column of more toxic blooms, validating recent global studies and indicating that phosphorous is not the only factor to be monitored in bloom mitigation. Blooms occurred at low TN: TP ratios and at temperatures above 12°C. Nitrogen was linked to toxicity and temperature also had a positive effect on bloom occurrence and toxicity. Microcystis was the most ubiquitous of the cyanobacterial strains reported in Africa and the one most frequently toxic. Cylindrospermopsis was reported more in the dry, north and western parts of the continent countries as opposed to the rest of the continent, whilst Anabaena was more frequent on the south eastern regions. In light of the entire continent, the inadequacy in reported blooms and advances in this area of research require critical intervention and action.


Assuntos
Cianobactérias/fisiologia , Pesquisa , Angola , Cylindrospermopsis/fisiologia , Microcystis/fisiologia , Pesquisa/tendências , Microbiologia da Água , Qualidade da Água
4.
Artigo em Inglês | MEDLINE | ID: mdl-25571295

RESUMO

Blinds and severe visual impairments can utilize tactile sticks to assist their walking. However, they cannot fully understand the dangling objects in front of their walking routes. This research proposed a mobile real-time dangling objects sensing (RDOS) prototype, which is located on the cap to sense any front barrier. This device utilized cheap ultrasonic sensor to act as another complement eye for blinds to understand the front dangling objects. Meanwhile, the RDOS device can dynamically adjust the sensor's front angle that is depended on the user's body height and promote the sensing accuracy. Meanwhile, two major required algorithms, height-angle measurement and ultrasonic sensor alignment, are proposed with this prototype. The research team also integrated the RDOS device prototype with mobile Android devices by communicating with Bluetooth to record the walking route.


Assuntos
Próteses Visuais , Atividades Cotidianas , Algoritmos , Humanos , Postura , Caminhada , Tecnologia sem Fio
5.
Environ Pollut ; 176: 244-53, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23434775

RESUMO

Streams impacted by acid mine drainage (AMD) typically present water exhibiting low pH and high metal concentrations. These factors result in the environmental degradation of watercourses. The objective of this study was to develop and evaluate an ecotoxicological screening tool (EST) to prioritise future remediation of streams impacted by AMD. The Bloubank stream drainage system in South Africa, served as study area for this purpose. In the initial EST development phase physicochemical variables were assessed while in the second phase, epilithic filamentous green algae biomass (chl-a mg m(-2)), diatoms and filamentous green algae community structures were employed as bioindicators as well as Daphnia magna toxicity assays. Using a weight of evidence approach, the first three sites receiving AMD were critically and seriously modified, followed by site 4 that was modified. Sites 1-3 with EST scores ≤70% were assessed as priority candidates for future restoration.


Assuntos
Monitoramento Ambiental/métodos , Mineração , Rios/química , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Daphnia , Ecotoxicologia , Metais/análise , Metais/toxicidade , Testes de Toxicidade , Poluentes Químicos da Água/análise
6.
J Anim Sci ; 89(11): 3460-72, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21705633

RESUMO

The discovery of postnatal mesenchymal stem cells (MSC) with their general multipotentiality has fueled much interest in the development of cell-based therapies. Proper identification of transplanted MSC is crucial for evaluating donor cell distribution, differentiation, and migration. Lack of an efficient marker of transplanted MSC has precluded our understanding of MSC-related regenerative studies, especially in large animal models such as pigs. In the present study, we produced transgenic pigs harboring an enhanced green fluorescent protein (EGFP) gene. The pigs provide a reliable and reproducible source for obtaining stable EGFP-labeled MSC, which is very useful for donor cell tracking after transplantation. The undifferentiated EGFP-tagged MSC expressed a greater quantity of EGFP while maintaining MSC multipotentiality. These cells exhibited homogeneous surface epitopes and possessed classic trilineage differentiation potential into osteogenic, adipogenic, and chondrogenic lineages, with robust EGFP expression maintained in all differentiated progeny. Injection of donor MSC can dramatically increase the thickness of infarcted myocardium and improve cardiac function in mice. Moreover, the MSC, with their strong EGFP expression, can be easily distinguished from the background autofluorescence in myocardial infarcts. We demonstrated an efficient, effective, and easy way to identify MSC after long-term culture and transplantation. With the transgenic model, we were able to obtain stem or progenitor cells in earlier passages compared with the transfection of traceable markers into established MSC. Because the integration site of the transgene was the same for all cells, we lessened the potential for positional effects and the heterogeneity of the stem cells. The EGFP-transgenic pigs may serve as useful biomedical and agricultural models of somatic stem cell biology.


Assuntos
Animais Geneticamente Modificados/genética , Proteínas de Fluorescência Verde/genética , Células-Tronco Mesenquimais/citologia , Suínos/genética , Adipogenia/genética , Adipogenia/fisiologia , Animais , Animais Geneticamente Modificados/fisiologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Condrogênese/genética , Condrogênese/fisiologia , Ecocardiografia/veterinária , Feminino , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica/veterinária , Transplante de Células-Tronco Mesenquimais/métodos , Transplante de Células-Tronco Mesenquimais/normas , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência/veterinária , Infarto do Miocárdio/terapia , Osteogênese/genética , Osteogênese/fisiologia , Distribuição Aleatória , Suínos/fisiologia
7.
Bioresour Technol ; 101(16): 6329-35, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20400299

RESUMO

This study aims at investigating the effects of MSW incinerator fly ash (FA) and bottom ash (BA) on the anaerobic co-digestion of OFMSW with FA or BA. It also simulates the biogas production from various dosed and control bioreactors. Results showed that suitable ashes addition (FA/MSW 10 and 20 g L(-1) and BA/MSW 100 g L(-1)) could improve the MSW anaerobic digestion and enhance the biogas production rates. FA/MSW 20 g L(-1) bioreactor had the higher biogas production and rate implying the potential option for MSW anaerobic co-digestion. Modeling studies showed that exponential plot simulated better for FA/MSW 10 g L(-1) and control bioreactors while Gaussian plot was applicable for FA/MSW 20 g L(-1) one. Linear and exponential plot of descending limb both simulated better for BA/MSW 100 g L(-1) bioreactor. Modified Gompertz plot showed higher correlation of biogas accumulation than exponential rise to maximum plot for all bioreactors.


Assuntos
Anaerobiose , Biocombustíveis , Reatores Biológicos , Compostos Orgânicos/química
8.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 4731-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17946647

RESUMO

The paper presents an integrated, distributed Healthcare Enterprise Information Portal (HEIP) and Hospital Information Systems (HIS) framework over wireless/wired infrastructure at National Taiwan University Hospital (NTUH). A single sign-on solution for the hospital customer relationship management (CRM) in HEIP has been established. The outcomes of the newly developed Outpatient Information Systems (OIS) in HIS are discussed. The future HEIP blueprints with CRM oriented features: e-Learning, Remote Consultation and Diagnosis (RCD), as well as on-Line Vaccination Services are addressed. Finally, the integrated HEIP and HIS architectures based on the middleware technologies are proposed along with the feasible approaches. The preliminary performance of multi-media, time-based data exchanges over the wireless HEIP side is collected to evaluate the efficiency of the architecture.


Assuntos
Sistemas de Informação Hospitalar , Telemedicina/instrumentação , Redes de Comunicação de Computadores , Sistemas Computacionais , Computadores , Sistemas de Gerenciamento de Base de Dados , Desenho de Equipamento , Humanos , Sistemas de Informação , Internet , Sistemas Computadorizados de Registros Médicos , Pacientes Ambulatoriais , Software , Taiwan , Telemedicina/métodos
9.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 3354-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271001

RESUMO

This paper presents our application of Health Level Seven (HL7) standard in a collaborative healthcare information system (HIS). Originally, we have used HL7 message events to flow among HIS systems. Later on, we found that the message interface management become a nightmare for system engineers. Recently, we extract the spirit of HL7 standard to create an alterative HL7 usage over the web services, and reorganize our traditional programmer team into a software collaborative team (SCT) to manage the project schedules effectively. Gradually, this new methodology had already been accepted by most of our system engineers. Moreover, the application of this methodology at National Taiwan University Hospital (NTUH) has shown that it can decrease the HIS system development cost.

10.
Burns ; 28(7): 691-5, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12417168

RESUMO

The evolution of care delivered by a multidisciplinary burns team is a function of the effectiveness of the professional communication between team members. In this exercise, we have explored concepts and communication between nurses and doctors in a burns team. Loosely structured weekly meetings were held over a 4-month period. The explicit objective was to determine and define the current model of burns care in a regional burn centre. The implicit objective, however, was to develop a mutual appreciation of actual and potential problems in communication. Consensus task identification was achieved at the end of each meeting with full compliance in completing the tasks before the next meeting. Although there was a unanimous commitment to the team concept, traditional, professional, paradigms persist. For nurses, the concept of holistic modelling predominated, whilst the disease centred paradigm remained the focus of medical modelling. Linguistic, cultural and professional barriers to effective communication were identified but did not readily conform to prior expectations. Experience in burns care can transcend these barriers more effectively than a common culture or profession. In conclusion, team work and team building is a complex process that can benefit from an ongoing process of re-evaluation. An obvious yet common error is to assume a level of mutual understanding that does not in fact exist. Stepping aside to re-explore fundamental principles on which team members base their personal and professional practice can help in elucidating and determining new paradigms of care, which can be evaluated and appropriately implemented. The consensus conclusion was that this approach was a very valuable investment in time in pursuing excellence in the field of burns care.


Assuntos
Queimaduras/terapia , Corpo Clínico Hospitalar/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Equipe de Assistência ao Paciente/organização & administração , Relações Médico-Enfermeiro , Atitude do Pessoal de Saúde , Unidades de Queimados/organização & administração , China , Comunicação , Formação de Conceito , Humanos , Modelos Teóricos
11.
Opt Lett ; 18(9): 678-80, 1993 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19802237

RESUMO

We developed a point-fluorescent-source-based white-light interferometer for high-resolution reflectometry, range-gating imaging, and group-velocity-dispersion measurement. The laser-pumped point fluorescent source has 9 mW of power and a spatial coherence of 0.97, which allows it to be used like a laser beam. Owing to its 40-nm FWHM spectral width, the width of its temporal autocorrelation is only 19 fs, which corresponds to that of 14-fs Gaussian pulses.

12.
Crit Care Med ; 12(8): 664-8, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6430648

RESUMO

Intravascular volume expansion was studied in 59 critically ill patients with a wide variety of sepsis and in a small group of 12 patients with peritonitis; either 500 ml of 5% albumin solution or 2 units of packed red blood cells were given over a 60-min period. During the 2-h period after volume loading, significant increases in mean arterial pressure (MAP), pulmonary capillary wedge pressure (WP), central venous pressure (CVP), and oxygen consumption (VO2) were observed. One hour after fluid administration MAP had risen from 72 +/- 16 (SD) at baseline to 78 +/- 17 mm Hg (p less than .01), WP from 9 +/- 5 to 16 +/- 7 mm Hg (p less than .05), CVP from 7 +/- 4 to 9 +/- 4 mm Hg (p less than .05) and VO2 from 132 +/- 19 to 148 +/- 31 ml/min X m2 (p less than .01). Improvement in VO2 after volume loading is consistent with the concept that circulatory problems in sepsis result in less VO2 than is needed and that intravascular volume expansion in normovolemic septic patients may improve peripheral perfusion as measured by oxygen uptake.


Assuntos
Infecções Bacterianas/terapia , Hidratação , Hemodinâmica , Peritonite/terapia , Respiração , Adulto , Idoso , Infecções Bacterianas/metabolismo , Infecções Bacterianas/fisiopatologia , Transfusão de Sangue , Dióxido de Carbono/sangue , Débito Cardíaco , Transfusão de Eritrócitos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Oxigênio/metabolismo , Peritonite/metabolismo , Peritonite/fisiopatologia , Substitutos do Plasma/uso terapêutico
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