A novel concept for long-term pre-storage and release of liquids for pressure-driven lab-on-a-chip devices

A microfluidic platform that integrates pressure-driven flow with electroosmotic-driven flow and inline filters was developed to ease the burden of performing long-term affinity assays.

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Flow Control Using Active Dimples

Fluids Engineering ◽

10.1115/imece2004-62528 ◽

2004 ◽

Cited By ~ 1

Author(s):

Natalie Udovidchik ◽

Sebastien Lambert

Keyword(s):

Flow Control ◽

Aerodynamic Drag ◽

Spherical Shape ◽

Reynolds Numbers ◽

Synthetic Jets ◽

Actuation Frequency ◽

Flux Change ◽

Novel Concept ◽

Smart Surface

In this study, a novel concept of using active dimples for flow control is introduced. It is widely known that dimples on a golf ball dramatically reduce its aerodynamic drag. They are much more effective than surface roughness since the hollow spherical shape produces cavity flow, thus the drag coefficient remains relatively constant at higher Reynolds numbers. It has also been shown by previous studies that by use of circular-arc grooves or dimples, the separation point on a cylinder could be regulated and drag reduced due to the re-circulation occurring in the dimpled surface. Another approach to flow separation that uses the concept of momentum-flux change by near-wall manipulation is an active one, such as synthetic jets or acoustical excitation. The long-term goal of this study is to merge these two approaches and create a continuous smart surface that would have active depressions, which would then be actuated at desired frequencies and conform to a desired shape for optimal results. Current investigation had only touched the tip of the iceberg of this new and unexplored field. In order to begin to comprehend the complexity of the fluid mechanics of the active dimples, a dual focus had been outlined in this study. The first focused on the investigation of a single active dimple on a flat plate, while the latter investigated the effect of a row consisting of such devices on a circular cylinder. The main factors of interest are optimal actuation frequency and dimple positioning relative to the freestream.

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A novel concept of the integrated fluorescence detection system and its application in a lab-on-a-chip microdevice

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2006.04.069 ◽

2006 ◽

Vol 118 (1-2) ◽

pp. 11-19 ◽

Cited By ~ 48

Author(s):

Radoslaw Mazurczyk ◽

Julien Vieillard ◽

Aude Bouchard ◽

Benjamin Hannes ◽

Stanislas Krawczyk

Keyword(s):

Fluorescence Detection ◽

Detection System ◽

Lab On A Chip ◽

Novel Concept ◽

Fluorescence Detection System

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Liquid Calcium Chloride Solar Storage: Concept and Analysis

Journal of Solar Energy Engineering ◽

10.1115/1.4003292 ◽

2011 ◽

Vol 133 (1) ◽

Cited By ~ 19

Author(s):

Josh A. Quinnell ◽

Jane H. Davidson ◽

Jay Burch

Keyword(s):

Calcium Chloride ◽

Fluid Dynamic ◽

Storage System ◽

Internal Heat ◽

Liquid Desiccant ◽

Internal Heat Exchanger ◽

Liquid Calcium ◽

Environmentally Safe ◽

Novel Concept

Aqueous calcium chloride has a number of potential advantages as a compact and long-term solar storage medium compared with sensibly heated water. The combination of sensible and chemical binding energy of the liquid desiccant provides higher energy densities and lower thermal losses, as well as a temperature lift during discharge via an absorption heat pump. Calcium chloride is an excellent choice among desiccant materials because it is relatively inexpensive, nontoxic, and environmentally safe. This paper provides an overview of its application for solar storage and presents a novel concept for storing the liquid desiccant in a single storage vessel. The storage system uses an internal heat exchanger to add and discharge thermal energy and to help manage the mass, momentum, and energy transfer in the tank. The feasibility of the proposed concept is demonstrated via a computational fluid dynamic study of heat and mass transfer in the system over a range of Rayleigh, Lewis, Prandtl, and buoyancy ratio numbers expected in practice.

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A QCM-Based Lab-on-a-Chip Device for Real Time Characterization of Shear-Induced Platelets Adhesion and Aggregation

ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels ◽

10.1115/icnmm2012-73205 ◽

2012 ◽

Author(s):

Hongwei Sun ◽

Pengtao Wang ◽

Moli Liu ◽

Jin Xu

Keyword(s):

Real Time ◽

Protein Interaction ◽

Platelet Adhesion ◽

Lab On A Chip ◽

Platelet Surface ◽

Surface Receptor ◽

Von Willebrand ◽

The Impact ◽

Willebrand Factor

The long-term goal of this project is to develop a microfluidic device integrated with a quartz crystal microbalance (QCM) sensor to perform real-time monitoring of platelet adhesion and aggregation under various hemodynamic conditions. This Lab-On-a-Chip device was fabricated with softlithography technique and plasma bonding. The gold sensing surface (electrode) of QCM sensor was embedded in the sensing area of microchannel, in which different fluid solutions were driven through to induce required shear flows for protein interaction study. The time-dependent (transient) frequency shift upon flowing blood samples was monitored to characterize the dynamic process of the platelet adhesion and protein interaction. The interaction between recombinant platelet surface receptor glycoprotein Ibα (GPIbα) and von Willebrand factor (vWF) were investigated under both static and dynamic flow conditions. It was found that the association process is much faster than disassociation process. This device functions as a powerful platform for studying the impact of flow pattern and shear stress on platelet function and GPIbα and vWF interaction, and potentially serves as a prototype for cardiovascular diagnostic purposes.

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A 60-Year-Old Female With Metastatic Malignant Melanoma of the Scalp Responding to Ipilimumab

Plastic Surgery Case Studies ◽

10.1177/2513826x17751116 ◽

2018 ◽

Vol 4 ◽

pp. 2513826X1775111

Author(s):

Sarah Lohrenz ◽

Jennifer Crawford ◽

Shawki Souf

Keyword(s):

Malignant Melanoma ◽

Treatment Options ◽

Poor Response ◽

Metastatic Malignant Melanoma ◽

Advanced Stage ◽

Free Response ◽

First Case ◽

Promising Treatment ◽

Novel Concept

Melanoma is an aggressive disease that accounts for approximately 75% of skin cancer-related deaths. In the past, treatment options for patients with advanced stage melanoma have been limited with poor response rate and failure to improve overall survival (OS). Immunotherapy is a promising treatment that has been shown to improve OS and in cases produce durable remissions—a novel concept in the treatment of advanced melanoma. We report a case of advanced stage metastatic malignant melanoma of the scalp with a durable (31 months) response to ipilimumab immunotherapy. This is the first case study reporting long-term, progression-free response to ipilimumab in metastatic melanoma without side effects of therapy. This case adds to the evidence supporting early referral and initiation of ipilimumab in patients who can tolerate it, with the goal of producing a sustained treatment-free response and preserved quality of life.

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Leaf Multi-Element Network Reveals the Change of Species Dominance Under Nitrogen Deposition

Frontiers in Plant Science ◽

10.3389/fpls.2021.580340 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jiahui Zhang ◽

Tingting Ren ◽

Junjie Yang ◽

Li Xu ◽

Mingxu Li ◽

...

Keyword(s):

Climate Change ◽

Global Climate Change ◽

Global Climate ◽

N Deposition ◽

High Plasticity ◽

Species Dominance ◽

Novel Approach ◽

Novel Concept ◽

Species Specific

Elements are important functional traits reflecting plant response to climate change. Multiple elements work jointly in plant physiology. Although a large number of studies have focused on the variation and allocation of multiple elements in plants, it remains unclear how these elements co-vary to adapt to environmental change. We proposed a novel concept of the multi-element network including the mutual effects between element concentrations to more effectively explore the alterations in response to long-term nitrogen (N) deposition. Leaf multi-element networks were constructed with 18 elements (i.e., six macronutrients, six micronutrients, and six trace elements) in this study. Multi-element networks were species-specific, being effectively discriminated irrespective of N deposition level. Different sensitive elements and interactions to N addition were found in different species, mainly concentrating on N, Ca, Mg, Mn, Li, Sr, Ba, and their related stoichiometry. Interestingly, high plasticity of multi-element network increased or maintained relative aboveground biomass (species dominance) in community under simulated N deposition, which developed the multi-element network hypothesis. In summary, multi-element networks provide a novel approach for exploring the adaptation strategies of plants and to better predict the change of species dominance under altering nutrient availability or environmental stress associated with future global climate change.

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The Compression Anastomotic Ring-Locking Procedure: A Novel Technique for Creating a Sutureless Colonic Anastomosis

European Surgical Research ◽

10.1159/000368354 ◽

2014 ◽

Vol 54 (3-4) ◽

pp. 139-147 ◽

Cited By ~ 3

Author(s):

Dadi Vilhjalmsson ◽

Per Olofsson ◽

Ingvar Syk ◽

Henrik Thorlacius ◽

Anders Grönberg

Keyword(s):

Colonic Anastomosis ◽

Bursting Pressure ◽

Stricture Formation ◽

Compression Pressure ◽

Long Term Follow Up ◽

Surgical Device ◽

Novel Concept ◽

Macroscopic Examination

Background/Aim: Compression anastomoses might represent an improvement over traditional hand-sewn or stapled techniques. Herein, we describe a novel concept of sutureless colonic anastomosis named compression anastomotic ring-locking procedure (CARP). Materials and Methods: The surgical device consists of two anastomotic rings and their associated helping tools, facilitating the placement of the rings into the intestinal ends. Furthermore, four catheters are connected to the surgical device, allowing the evaluation of the anastomosis during and after surgery. A total of 31 pigs underwent a low colocolic anastomosis using the anastomotic rings. The compression pressure was measured perioperatively and up to 96 h after surgery. Anastomotic integrity and morphology were analyzed by use of radiology and histology, respectively. A long-term follow-up was conducted in a subgroup of pigs up to 108 days after surgery when the bursting pressure and stricture formation were examined. Results: All animals recovered uneventfully, and macroscopic examination revealed intact anastomoses without signs of pathological inflammation or adhesions. The perioperative compression pressure was inversely proportional to the gap size between the anastomotic rings. For example, an anastomotic gap of 1.5 mm created a colonic anastomosis with a perioperative compression pressure of 91 mbar, which remained constant for up to 48 h and resulted in a markedly increased compression pressure. Contrast infusion via the catheters effectively visualized the anastomoses, and no leakage was detected within the study. The surgical device was spontaneously evacuated from the intestines within 6 days after surgery. Histology showed collagen bridging of the anastomoses already 72 h after surgery. Long-term follow-up (54-108 days) revealed no stricture formation in the anastomoses, and the bursting pressure ranged from 120 to 235 mbar. The majority of bursts (10/12) occurred distant from the anastomoses. Conclusion: We conclude that the surgical device associated to CARP is safe and efficient for creating colonic anastomoses. Further studies in patients undergoing colorectal surgery are warranted.

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