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1.
Laryngoscope Investig Otolaryngol ; 8(6): 1516-1521, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38130260

RESUMO

Objective: In recent years, the video sharing app TikTok has become a new venue for health care providers and medical educators. Research on health care information within the app has primarily focused on cosmetic and plastic surgery content. TikTok could potentially be a tool used to educate the public on otolaryngology-related topics. This study is the first to analyze the quality and quantity of otolaryngology-related TikTok content. Methods: A cross-sectional study of TikTok accounts using otolaryngology-related hashtags within the preceding 6 months was conducted on February 4, 2023. Deductive qualitative analysis was performed between two coders to identify themes of the accounts and their content. Results: A total of 47 accounts were selected for analysis. Facial plastic surgery was the most represented specialty (n = 20; 43%) and pediatric otolaryngology the least represented (n = 1; 2%). Content posted was primarily educational in nature (n = 30; 64%) and 66% (n = 31) of content creators advertised contact information in their account biography. The majority of accounts were in English (n = 30; 64%) and originated in the United States (n = 30; 64%). More accounts were run by male (n = 29; 62%) than female content creators. Conclusion: Otolaryngology is a broad specialty with unequal representation of the related subspecialties on TikTok, a popular social media platform. The majority of current content focuses on patient education in facial plastic surgery. Future studies are warranted to examine the potential growth and impact of otolaryngology content on this video-based platform. Level of Evidence: 2.

2.
Biomed Phys Eng Express ; 9(6)2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37657422

RESUMO

Oscillometric blood pressure measurement devices are not directly traceable to primary standards. Currently, device accuracy is measured by comparison between a sample device and reference measurements in a clinical trial. We researched in this study the potential for an alternative evaluation with a simulator. Our research simulator was studied for repeatability and accuracy in delivering simulated blood pressure pulses. Clinical cuff pressure measurements were obtained, along with simultaneous recordings of oscillometric pulse waveforms, spanning the clinical range of cuff pressures, pulse intervals and pulse shapes. Oscillometric pulse peak amplitudes ranged from 1.1 to 3.6 mmHg. Simulated repeatability results showed an average Standard Deviation (SD) for pulse peaks of 0.018 mmHg; 1.0% of peak amplitudes. Comparing simulated pulse shapes, the average repeat SD was 0.015 mmHg; 0.8% of the normalised pulse shapes. The simulated accuracy results had a mean error of - 0.014 ± 0.042 mmHg with a mean accuracy of 97.8%. For pulse shape the corresponding values were - 0.104 ± 0.071 mmHg with a mean accuracy of 95.4%. The correlation between the reference and simulated pulse shapes ranged from 0.991 to 0.996 (all p < 0.00003), with a mean 0.994. We conclude that oscillometric pulses can be reproduced with high repeatability and high accuracy with our research simulator. The extended uncertaintyU(psim) = 0.3 mmHg for the simulated pulses is dominated by the uncertainty (64%) of the clinical reference data. These results underpin the potential of the simulator to become a secondary standard for millions of oscillometric sphygmomanometers.


Assuntos
Reprodução , Esfigmomanômetros , Pressão Sanguínea , Frequência Cardíaca , Incerteza
3.
J Environ Manage ; 346: 118997, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37769367

RESUMO

Various tools and techniques are used by environmental managers and planning agencies to make land use decisions that balance different and often competing goals. Multiple goals, or objectives, are generally challenging to address because there is likely no single optimal solution, but rather a range of possible Pareto (or tradeoff) solutions. Considerable attention has focused on software and approaches that rely on heuristic methods to generate solutions for land use planning problems with multiple objectives. While fast and accessible, there remain uncertainties about the quality of solutions obtained by these heuristic methods and whether they are indeed meeting the needs of environmental managers. This paper explores forest treatment planning for wildfire risk mitigation seeking to balance multiple objectives when the spatial pattern of treatment is restricted. Solution quality of one widely employed forest planning tool is evaluated (using measures of completeness, inferiority, and maximum gap) under a range of geographic settings and problem sizes. The findings indicate that obtained solutions are suboptimal, and fail to represent the full spectrum of tradeoffs possible.

4.
J Funct Biomater ; 14(6)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37367293

RESUMO

Implantable electrochemical sensors that enable the real-time detection of significant biomarkers offer huge potential for the enhancement and personalisation of therapies; however, biofouling is a key challenge encountered by any implantable system. This is particularly an issue immediately after implantation, when the foreign body response and associated biofouling processes are at their most active in passivating a foreign object. Here, we present the development of a sensor protection and activation strategy against biofouling, based on coatings consisting of a pH-triggered, dissolvable polymer, that covered a functionalised electrode surface. We demonstrate that reproducible delayed sensor activation can be achieved, and that the length of this delay can be controlled by the optimisation of coating thickness, homogeneity and density through tuning of the coating method and temperature. Comparative evaluation of the polymer-coated and uncoated probe-modified electrodes in biological media revealed significant improvements in their anti-biofouling characteristics, demonstrating that this offers a promising approach to the design of enhanced sensing devices.

5.
JMIR Form Res ; 7: e45188, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37347520

RESUMO

BACKGROUND: The Ending the HIV Epidemic initiative in the United States relies on HIV hotspots to identify where to geographically target new resources, expertise, and technology. However, interventions targeted at places with high HIV transmission and infection risk, not just places with high HIV incidence, may be more effective at reducing HIV incidence and achieving health equity. OBJECTIVE: We described the implementation and validation of a web-based activity space survey on HIV risk behaviors. The survey was intended to collect geographic information that will be used to map risk behavior hotspots as well as the geography of sexual networks in Los Angeles County. METHODS: The survey design team developed a series of geospatial questions that follow a 3-level structure that becomes more geographically precise as participants move through the levels. The survey was validated through 9 cognitive interviews and iteratively updated based on participant feedback until the saturation of topics and technical issues was reached. RESULTS: In total, 4 themes were identified through the cognitive interviews: functionality of geospatial questions, representation and accessibility, privacy, and length and understanding of the survey. The ease of use for the geospatial questions was critical as many participants were not familiar with mapping software. The inclusion of well-known places, landmarks, and road networks was critical for ease of use. The addition of a Google Maps interface, which was familiar to many participants, aided in collecting accurate and precise location information. The geospatial questions increased the length of the survey and warranted the inclusion of features to simplify it and speed it up. Using nicknames to refer to previously entered geographic locations limited the number of geospatial questions that appeared in the survey and reduced the time taken to complete it. The long-standing relationship between participants and the research team improved comfort to disclose sensitive geographic information related to drug use and sex. Participants in the cognitive interviews highlighted how trust and inclusive and validating language in the survey alleviated concerns related to privacy and representation. CONCLUSIONS: This study provides promising results regarding the feasibility of using a web-based mapping survey to collect sensitive location information relevant to ending the HIV epidemic. Data collection at several geographic levels will allow for insights into spatial recall of behaviors as well as future sensitivity analysis of the spatial scale of hotspots and network characteristics. This design also promotes the privacy and comfort of participants who provide location information for sensitive topics. Key considerations for implementing this type of survey include trust from participants, community partners, or research teams to overcome concerns related to privacy and comfort. The implementation of similar surveys should consider local characteristics and knowledge when crafting the geospatial components.

6.
Lett Spat Resour Sci ; 16(1): 8, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910584

RESUMO

It is well established that a variety of physical distancing measures are invaluable as part of the overall response to pandemics. COVID-19 is the most recent such pandemic, a respiratory disease transmitted through interaction, necessitating steps to minimize or eliminate the potential for exposure. Of course, this is driven by a desire to keep the economy moving, allow for social activity, continue education, support the livelihoods of individuals, etc. Regional science and supporting analytics have an important role in managing activity through the development and application of methods that enable spatial interaction that mitigates transmission. This paper details methods to plan for physical distancing at micro-scales, enabling the return of social, economic, entertainment, etc. activities. Geographic information systems combined with spatial optimization offers important spatial coronametrics for the mitigation of risk in disease transmission. Applications detailing office space occupancy and travel along with room seating are highlighted.

7.
J Hum Hypertens ; 37(2): 93-100, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35637256

RESUMO

Automated 'oscillometric' blood pressure (BP) measuring devices (BPMDs) were developed in the 1970s to replace manual auscultatory BP measurement by mercury sphygmomanometer. Automated BPMDs that have passed accuracy testing versus a reference auscultatory sphygmomanometer using a scientifically accepted validation protocol are recommended for clinical use globally. Currently, there are many thousands of unique automated BPMDs manufactured by hundreds of companies, with each device using proprietary algorithms to estimate BP and using a method of operation that is largely unchanged since inception. Validated automated BPMDs provide similar BP values to those recorded using manual auscultation albeit with potential sources of error mostly associated with using empirical algorithms to derive BP from waveform pulsations. Much of the work to derive contemporary BP thresholds and treatment targets used to manage cardiovascular disease risk was obtained using automated BPMDs. While there is room for future refinement to improve accuracy for better individual risk stratification, validated BPMDs remain the recommended standard for office and out-of-office BP measurement to be used in hypertension diagnosis and management worldwide.


Assuntos
Determinação da Pressão Arterial , Hipertensão , Humanos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Hipertensão/diagnóstico , Esfigmomanômetros , Oscilometria
8.
J Hypertens ; 40(8): 1449-1460, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35708294

RESUMO

BACKGROUND: Many cuffless blood pressure (BP) measuring devices are currently on the market claiming that they provide accurate BP measurements. These technologies have considerable potential to improve the awareness, treatment, and management of hypertension. However, recent guidelines by the European Society of Hypertension do not recommend cuffless devices for the diagnosis and management of hypertension. OBJECTIVE: This statement by the European Society of Hypertension Working Group on BP Monitoring and Cardiovascular Variability presents the types of cuffless BP technologies, issues in their validation, and recommendations for clinical practice. STATEMENTS: Cuffless BP monitors constitute a wide and heterogeneous group of novel technologies and devices with different intended uses. Cuffless BP devices have specific accuracy issues, which render the established validation protocols for cuff BP devices inadequate for their validation. In 2014, the Institute of Electrical and Electronics Engineers published a standard for the validation of cuffless BP devices, and the International Organization for Standardization is currently developing another standard. The validation of cuffless devices should address issues related to the need of individual cuff calibration, the stability of measurements post calibration, the ability to track BP changes, and the implementation of machine learning technology. Clinical field investigations may also be considered and issues regarding the clinical implementation of cuffless BP readings should be investigated. CONCLUSION: Cuffless BP devices have considerable potential for changing the diagnosis and management of hypertension. However, fundamental questions regarding their accuracy, performance, and implementation need to be carefully addressed before they can be recommended for clinical use.


Assuntos
Determinação da Pressão Arterial , Hipertensão , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Calibragem , Humanos , Hipertensão/diagnóstico , Hipertensão/terapia , Esfigmomanômetros
9.
J Geogr Syst ; 24(2): 223-240, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035280

RESUMO

Over the past 20 years, professional and collegiate baseball has undergone a transformation, with statistics and analytics increasingly factoring into most of the decisions being made on the field. One particular example of the increased role of analytics is in the positioning of outfielders, who are tasked with tracking down balls hit to the outfield to record outs and minimize potential offensive damage. This paper explores the potential of location analytics to enhance the strategic positioning of players, enabling improved response and performance. We implement a location optimization model to analyze collegiate ball-tracking data, seeking outfielder locations that simultaneously minimize the average distance to a batted ball and maximize the weighted importance of batted ball coverage within a response standard. Trade-off outfielder configurations are compared to observed fielder positioning, finding that location models and spatial optimization can lead to performance improvements ranging from 1 to 3%, offering a significant strategic advantage over the course of a season.

10.
Biosens Bioelectron ; 197: 113728, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34763151

RESUMO

The development of robust implantable sensors is important in the successful advancement of personalised medicine as they have the potential to provide in situ real-time data regarding the status of health and disease and the effectiveness of treatment. Tissue pH is a key physiological parameter and herein, we report the design, fabrication, functionalisation, encapsulation and protection of a miniaturised, self-contained, electrochemical pH sensor system and characterisation of sensor performance. Notably for the first time in this environment the pH sensor was based on a methylene blue redox reporter which showed remarkable robustness, accuracy and sensitivity. This was achieved by encapsulation of a self-assembled monolayer containing methylene blue entrapped within a Nafion layer. Another powerful feature was the incorporation, within the same implanted device, of a fabricated on-chip Ag/AgCl reference electrode - vital in any electrochemical sensor, but often ignored. When utilised in vivo, the sensor allowed accurate tracking of externally induced pH changes within a naturally occurring ovine lung cancer model, and correlated well with single point laboratory measurements made on extracted arterial blood, whilst enabling in vivo time-dependent measurements. The sensors functioned robustly whilst implanted, and maintained in vitro function once extracted and together, these results demonstrate proof-of-concept of the ability to sense real-time intratumoral tissue pH changes in vivo.


Assuntos
Técnicas Biossensoriais , Azul de Metileno , Animais , Técnicas Eletroquímicas , Concentração de Íons de Hidrogênio , Oxirredução , Ovinos
11.
Micromachines (Basel) ; 12(7)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34357220

RESUMO

Anastomotic leakage (AL) is a common and dangerous post-operative complication following intestinal resection, causing substantial morbidity and mortality. Ischaemia in the tissue surrounding the anastomosis is a major risk-factor for AL development. Continuous tissue oxygenation monitoring during the post-operative recovery period would provide early and accurate early identification of AL risk. We describe the construction and testing of a miniature implantable electrochemical oxygen sensor that addresses this need. It consisted of an array of platinum microelectrodes, microfabricated on a silicon substrate, with a poly(2-hydroxyethyl methacrylate) hydrogel membrane to protect the sensor surface. The sensor was encapsulated in a biocompatible package with a wired connection to external instrumentation. It gave a sensitive and highly linear response to variations in oxygen partial pressure in vitro, although over time its sensitivity was partially decreased by protein biofouling. Using a pre-clinical in vivo pig model, acute intestinal ischaemia was robustly and accurately detected by the sensor. Graded changes in tissue oxygenation were also measurable, with relative differences detected more accurately than absolute differences. Finally, we demonstrated its suitability for continuous monitoring of tissue oxygenation at a colorectal anastomosis over a period of at least 45 h. This study provides evidence to support the development and use of implantable electrochemical oxygen sensors for post-operative monitoring of anastomosis oxygenation.

12.
Materials (Basel) ; 14(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207642

RESUMO

Neuronal patterning on microfabricated architectures has developed rapidly over the past few years, together with the emergence of soft biocompatible materials and tissue engineering scaffolds. Previously, we introduced a patterning technique based on serum and the biopolymer parylene-C, achieving highly compliant growth of primary neurons and astrocytes on different geometries. Here, we expanded this technique and illustrated that neuralized cells derived from mouse embryonic stem cells (mESCs) followed stripes of variable widths with conformity equal to or higher than that of primary neurons and astrocytes. Our results indicate the presence of undifferentiated mESCs, which also conformed to the underlying patterns to a high degree. This is an exciting and unexpected outcome, as molecular mechanisms governing cell and ECM protein interactions are different in stem cells and primary cells. Our study enables further investigations into the development and electrophysiology of differentiating patterned neural stem cells.

13.
J Pers Med ; 11(6)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070593

RESUMO

Development of an anastomotic leak (AL) following intestinal surgery for the treatment of colorectal cancers is a life-threatening complication. Failure of the anastomosis to heal correctly can lead to contamination of the abdomen with intestinal contents and the development of peritonitis. The additional care that these patients require is associated with longer hospitalisation stays and increased economic costs. Patients also have higher morbidity and mortality rates and poorer oncological prognosis. Unfortunately, current practices for AL diagnosis are non-specific, which may delay diagnosis and have a negative impact on patient outcome. To overcome these issues, research is continuing to identify AL diagnostic or predictive biomarkers. In this review, we highlight promising candidate biomarkers including ischaemic metabolites, inflammatory markers and bacteria. Although research has focused on the use of blood or peritoneal fluid samples, we describe the use of implantable medical devices that have been designed to measure biomarkers in peri-anastomotic tissue. Biomarkers that can be used in conjunction with clinical status, routine haematological and biochemical analysis and imaging have the potential to help to deliver a precision medicine package that could significantly enhance a patient's post-operative care and improve outcomes. Although no AL biomarker has yet been validated in large-scale clinical trials, there is confidence that personalised medicine, through biomarker analysis, could be realised for colorectal cancer intestinal resection and anastomosis patients in the years to come.

14.
PLoS One ; 15(12): e0243345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33275618

RESUMO

The coronavirus disease 2019 is a respiratory illness spread between people. A primary weapon for reducing or eliminating this disease involves physical distancing to thwart transmission. Efforts to keep the economy moving include enacting physical distancing strategies that will increase the safety of workplaces, schools, businesses, etc. Given that education is a critical economic sector that impacts essentially all other sectors in some way, this paper details a planning approach for classroom physical distancing supported by spatial optimization. Devising a configuration of desks and/or workspaces that are physically distant is a type of dispersion problem that can be formalized mathematically and solved. Planning efforts for a university campus serve to illustrate how spatial optimization can support safety enhancements.


Assuntos
COVID-19/prevenção & controle , Distanciamento Físico , Instituições Acadêmicas/tendências , COVID-19/transmissão , Infecções por Coronavirus/epidemiologia , Humanos , Modelos Teóricos , Pandemias , SARS-CoV-2
15.
Physiol Meas ; 41(7): 074001, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32784270

RESUMO

OBJECTIVE: It is accepted that changes in the peripheral pulse waveform characteristics occur with ageing. Pulse risetime is one important feature which has clinical value. However, it is unclear how it varies across the full age spectrum from child to senior and for different peripheral measurement sites. The objectives of this study were to determine the association between age and pulse risetime characteristics over an 8-decade age range at the ears, fingers, and toes, and to consider effects arising from differences in systolic blood pressure (SBP), height and heart rate. APPROACH: Multi-site photoplethysmography (MPPG) pulse waveforms were recorded non-invasively from the right and left ears, fingers, and toes of 304 normal healthy human subjects (range 6-87 years; 156 male and 148 female). SBP, height, and heart rate were also measured. Multi-site PPG pulse risetimes, and their site differences, were determined. MAIN RESULTS: Univariate regression analysis showed positive correlations with risetime for age (ears, fingers and toes: + 0.8, + 1.9, and + 1.1 ms/year, respectively), SBP (+0.5, + 1.3, and + 0.9 ms/mmHg) and height (+0.5, + 1.2, and + 1.0 ms/cm), but with a clear inverse association with heart rate (-1.8, - 2.5, and - 1.6 ms min) (P < 0.0001). No significant differences between male and female subjects were found for pulse risetime. SIGNIFICANCE: Normative multi-site PPG risetime characteristics have been defined in over 300 subjects and are shown to increase with age linearly up to the 8th decade. In contrast, we have shown that heart rate has a clear inverse relationship with risetime for all measurement sites.


Assuntos
Envelhecimento , Frequência Cardíaca , Fotopletismografia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Orelha , Feminino , Dedos , Humanos , Masculino , Pessoa de Meia-Idade , Pulso Arterial , Dedos do Pé , Adulto Jovem
16.
Animals (Basel) ; 10(7)2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32674253

RESUMO

Calf disbudding is a painful husbandry practice on dairy and beef cattle farms. An objective measurement of pain is useful to reliably evaluate the pain intensity and anti-nociceptive (analgesic) efficacy of therapeutic agents. The aim of this study was to investigate the changes in peripheral leucocyte inflammatory cytokine gene expression in calves after disbudding, and to assess whether the changes in cytokine gene expression could be an indicator of the efficacy of analgesic drugs. In a randomised controlled study, 16 calves (aged 31 to 41 days and weighing 58 to 73 kg), undergoing routine disbudding, were randomly allocated into two groups (n = 8 in each group). Calves in the control group received no analgesic, while those in the treatment group received 0.5 mg kg-1 meloxicam subcutaneously prior to disbudding. Disbudding was performed using an electric debudder. Blood (10 mL) was sampled from the jugular vein just before and 4 and 24 h post-disbudding, RNA was extracted from leukocytes, and the transcription of 12 genes of interest was assessed using nCounter gene expression assay. The results showed significantly higher transcription (compared to baseline values) of the studied genes (except CRH, IFNγ, and IL10) in the control group calves at either 4 or 24 h post-disbudding. The administration of meloxicam one hour before disbudding significantly attenuated the upregulation of IL6, PGHS2, TAC1, NOS1, and CRH gene transcription post-disbudding, while it did not suppress the elevated transcription of acute and pro-inflammatory cytokines such as IL1ß, IFNγ, IL8, and TNFα genes. In conclusion, nCounter gene expression assay seems to be a promising tool to study the expression of cytokine genes and thus could be used for the pre-clinical evaluation of novel analgesics.

17.
Explor Target Antitumor Ther ; 1(2): 71-100, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-36046070

RESUMO

Dysregulation of cellular pH is frequent in solid tumours and provides potential opportunities for therapeutic intervention. The acidic microenvironment within a tumour can promote migration, invasion and metastasis of cancer cells through a variety of mechanisms. Pathways associated with the control of intracellular pH that are under consideration for intervention include carbonic anhydrase IX, the monocarboxylate transporters (MCT, MCT1 and MCT4), the vacuolar-type H+-ATPase proton pump, and the sodium-hydrogen exchanger 1. This review will describe progress in the development of inhibitors to these targets.

18.
Analyst ; 145(3): 975-982, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31829318

RESUMO

Proteases are ideal target biomarkers as they have been implicated in many disease states, including steps associated with cancer progression. Electrochemical peptide-based biosensors have attracted much interest in recent years. However, the significantly large size of the electrodes typically used in most of these platforms has led to performance limitations. These could be addressed by the enhancements offered by microelectrodes, such as rapid response times, improved mass transport, higher signal-to-noise and sensitivity, as well as more localised and less invasive measurements. We present the production and characterisation of a miniaturised electrochemical biosensor for the detection of trypsin, based on 25 µm diameter Pt microelectrodes (rather than the ubiquitous Au electrodes), benchmarked by establishing the equivalent Pt macroelectrode response in terms of quantitative response to the protease, the kinetics of cleavage and the effects of non-specific protein binding and temperature. Interestingly, although there was little difference between Au and Pt macroelectrode response, significant differences were observed between the responses of the Pt macroelectrode and microelectrode systems indicative of increased reproducibility in the microelectrode SAM structure and sensor performance between the electrodes, increased storage stability and a decrease in the cleavage rate at functionalised microelectrodes, which is mitigated by measurement at normal body temperature. Together, these results demonstrate the robustness and sensitivity of the miniaturised sensing platform and its ability to operate within the clinically-relevant concentration ranges of proteases in normal and disease states. These are critical features for its translation into implantable devices.


Assuntos
Técnicas Biossensoriais/métodos , Peptídeos/metabolismo , Platina/química , Tripsina/análise , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas , Cinética , Microeletrodos , Miniaturização , Peptídeos/química , Temperatura , Tripsina/metabolismo
19.
Sensors (Basel) ; 19(19)2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31569712

RESUMO

Automatic Identification System (AIS) data could support ship movement analysis, and maritime network construction and dynamic analysis. This study examines the global maritime network dynamics from multi-layers (bulk, container, and tanker) and multidimensional (e.g., point, link, and network) structure perspectives. A spatial-temporal framework is introduced to construct and analyze the global maritime transportation network dynamics by means of big trajectory data. Transport capacity and stability are exploited to infer spatial-temporal dynamics of system nodes and links. Maritime network structure changes and traffic flow dynamics grouping are then possible to extract. This enables the global maritime network between 2013 and 2016 to be investigated, and the differences between the countries along the 21st-century Maritime Silk Road and other countries, as well as the differences between before and after included by 21st-century Maritime Silk Road to be revealed. Study results indicate that certain countries, such as China, Singapore, Republic of Korea, Australia, and United Arab Emirates, build new corresponding shipping relationships with some ports of countries along the Silk Road and these new linkages carry significant traffic flow. The shipping dynamics exhibit interesting geographical and spatial variations. This study is meaningful to policy formulation, such as cooperation and reorientation among international ports, evaluating the adaptability of a changing traffic flow and navigation environment, and integration of the maritime economy and transportation systems.

20.
Angew Chem Int Ed Engl ; 58(40): 14189-14192, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31397963

RESUMO

A ruthenium-based mitochondrial-targeting photosensitiser that undergoes efficient cell uptake, enables the rapid catalytic conversion of PtIV prodrugs into their active PtII counterparts, and drives the generation of singlet oxygen was designed. This dual mode of action drives two orthogonal cancer-cell killing mechanisms with temporal and spatial control. The designed photosensitiser was shown to elicit cell death of a panel of cancer cell lines including those showing oxaliplatin-resistance.


Assuntos
Antineoplásicos/farmacologia , Compostos Organoplatínicos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Pró-Fármacos/farmacologia , Oxigênio Singlete/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Catálise , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/química , Processos Fotoquímicos , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Oxigênio Singlete/química
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