This paper describes the fabrication and the performance of microfluidic paper-based electrochemical sensing devices (we call the microfluidic paper-based electrochemical devices, μPEDs). The μPEDs comprise paper-based microfluidic channels patterned by photolithography or wax printing, and electrodes screen-printed from conducting inks (e.g., carbon or Ag/AgCl). We demonstrated that the μPEDs are capable of quantifying the concentrations of various analytes (e.g., heavy-metal ions and glucose) in aqueous solutions. This low-cost analytical device should be useful for applications in public health, environmental monitoring, and the developing world.

No abstract

Bubbling up: Dissolution of CO(2) bubbles in a suspension of colloidal particles chemically induces the assembly of particles on the surface of shrunken bubbles, and thus yields rapid continuous formation of a colloidal armor. This approach maintains the high colloidal stability of particles in bulk, has increased productivity, and allows the formation of bubbles with precisely controlled dimensions.

Bubbling up: Dissolution of CO2 bubbles in a suspension of colloidal particles chemically induces the assembly of particles on the surface of shrunken bubbles, and thus yields rapid continuous formation of a colloidal armor. This approach maintains the high colloidal stability of particles in bulk, has increased productivity, and allows the formation of bubbles with precisely controlled dimensions.

BACKGROUND:The Canadian health care system provides equitable access to equivalent standards of care. The authors investigated to determine whether patients with breast cancer who had different socioeconomic status (SES) received different care and had different overall survival (OS) in Ontario, Canada. METHODS: Women who were diagnosed with breast cancer between 2004 and 2009 were identified from the Ontario Cancer Registry and linked to provincial databases to ascertain patient demographics, screening, diagnosis, treatment patterns, and survival. SES was defined as neighborhood income by postal code and was divided into income quintiles (Q1-Q5; with Q5 the highest SES quintile). Univariable and multivariable analyses were used to examine the associations between: 1) SES and mammogram screening and breast cancer treatments, and 2) SES and OS. RESULTS: In total, 34,776 patients with breast cancer who had information on disease stage available at diagnosis were identified. Seventy-six percent of women were aged >50 years. Patients with higher SES were more likely to be diagnosed at an earlier stage (Q5 [44.3%] vs Q1 [37.7%]; odds ratio [OR], 1.31; 95% confidence interval [CI], 1.23-1.41; P < .0001) and also were more likely to receive adjuvant chemotherapy (Q5 vs Q1: OR, 1.18; 95% CI, 1.10-1.26; P < .0001) and radiotherapy (Q5 vs Q1: OR, 1.24; 95% CI, 1.15-1.33; P < .0001). The 5-year OS rates for Q1 through Q5 were 80%, 81%, 82.2%, 83.9%, and 85.7%, respectively (P < .0001). After adjusting for patient demographics, cancer stage at diagnosis, adjuvant chemotherapy, trastuzumab, radiotherapy and surgery types, higher SES remained associated with better OS (P 5 .0017). CONCLUSIONS: In a universal health care system, higher SES is associated with greater screening and treatments and with better OS after adjusting for screening, cancer stage at diagnosis, and treatments. Cancer 2016;122:893-8.

No abstract

We report a new microfluidic strategy for the generation of small (<10 mm) microbubbles with a narrow size distribution. Our approach has the following features: (i) the generation of bubbles from gaseous CO 2 and (ii) the controllable dissolution of these bubbles until they reach a desired size. We examine the role of various factors on the formation and the extent of bubble dissolution and show that the final dimensions of bubbles are determined by the flow rate of the continuous aqueous phase and the acid-base equilibria established within the microchannels.

There is an increasing effort in the search and characterization of materials that can function as artificial three-dimensional cellular microenvironments. In particular, the encapsulation of cells in micrometer-size hydrogel particles (microgels) offers the ease of cell visualization, the transport of nutrients, and the ability to generate large combinatorial libraries of cellular microenvironments. In the present work, we report an atomic force microscopy (AFM) method for the characterization of an average Young's modulus and the stress relaxation time of micrometer-size polymer microgel particles. We studied the mechanical properties of agarose microgels with different polymer concentration at room temperature and 37 C (the temperature of cell culture). We examined the temporal variation in the Young modulus of cell-free and cell-laden microgels under physiological conditions. Furthermore, we correlated the mechanical properties of the microgels laden with a single carcinoma associated fibroblast (CAF) cell with the spatial distribution of collagen around the cell. This work is potentially useful for studies of changes in cellular microenvironments, when cells locally degrade the matrix or secrete molecules that change the mechanical properties of the matrix.