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Microfluidic Platform for Adherent Single Cell High-Throughput Screening
This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.Traditionally, in vitro investigations on biology and physiology of cells rely on averaging the
responses eliciting from heterogeneous cell populations, thus being unsuitable for assessing individual cell
behaviors in response to external stimulations. In the last years, great interest has thus been focused on single
cell analysis and screening, which represents a promising tool aiming at pursuing the direct and deterministic
control over cause-effect relationships guiding cell behavior. In this regard, a high-throughput microfluidic
platform for trapping and culturing adherent single cells was presented. A single cell trapping mechanism
was implemented based on dynamic variation of fluidic resistances. A round-shaped culture chamber
(Φ=250μm, h=25μm) was conceived presenting two connections with a main fluidic path: (i) an upper wide
opening, and (ii) a bottom trapping junction which modulates the hydraulic resistance. Several layouts of the
chamber were designed and computationally validated for the optimization of the single cell trapping
efficacy. The optimized chamber layouts were integrated in a polydimethylsiloxane (PDMS) microfluidic
platform presenting two main functionalities: (i) 288 chambers for trapping single cells, and (ii) a chaoticmixer
based serial dilution generator for delivering both soluble factors and non-diffusive molecules under
spatio-temporally controlled chemical patterns. The devices were experimentally validated and allowed for
trapping individual U87-MG (human glioblastoma-astrocytoma epithelial-like) cells and culturing them up to
3 days
Tripodal gold(I) polypyridyl complexes and their Cu+ and Zn2+ heterometallic derivatives. Effects on luminescence
Three gold(I) tripodal complexes containing the tris(2-pyridylmethyl)amine (TPA) ligand coordinated to Au-PR3 moieties (PR3 = 1,3,5-triaza-7-phosphatricyclo[3.3.1.13.7]decane, PTA (1), 3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane, DAPTA (2) and triphenylphosphane (3)) were prepared together with a cage-like structure containing triphosphane 1,1,1-tris(diphenylphosphinomethyl)ethane (4). The luminescence of these complexes has been studied and they show a red shift upon the formation of heterometallic complexes by reaction with Zn(NO3)2, CuCl and [Cu(CH3CN)4]BF4. The different coordination motifs of the Zn2+ and Cu+ heterometallic species and the resulting changes in the recorded absorption, emission and NMR spectra were analysed and supported by TD-DFT calculations
Shifting a Quantum Wire through a Disordered Crystal: Observation of Conductance Fluctuations in Real Space
A quantum wire is spatially displaced by suitable electric fields with
respect to the scatterers inside a semiconductor crystal. As a function of the
wire position, the low-temperature resistance shows reproducible fluctuations.
Their characteristic temperature scale is a few hundred millikelvin, indicating
a phase-coherent effect. Each fluctuation corresponds to a single scatterer
entering or leaving the wire. This way, scattering centers can be counted one
by one.Comment: 4 pages, 3 figure
Evaluation of a large set of patients with Autoimmune Polyglandular Syndrome from a single reference centre in context of different classifications
Purpose: To characterize patients with APS and to propose a new approach for their follow-up. Query ID="Q1" Text="Please check the given names and familynames." Methods: Monocentric observational retrospective study enrolling patients referred to the Outpatients clinic of the Units of Endocrinology, Diabetology, Gastroenterology, Rheumatology and Clinical Immunology of our Hospital for Autoimmune diseases. Results: Among 9852 patients, 1174 (11.9%) [869 (73.9%) female] were diagnosed with APS. In 254 subjects, the diagnosis was made at first clinical evaluation (Group 1), all the other patients were diagnosed with a mean latency of 11.3 ± 10.6 years (Group 2). Group 1 and 2 were comparable for age at diagnosis (35.7 ± 16.3 vs. 40.4 ± 16.6 yrs, p =.698), but different in male/female ratio (81/173 vs 226/696, p =.019). In Group 2, 50% of patients developed the syndrome within 8 years of follow-up. A significant difference was found after subdividing the first clinical manifestation into the different outpatient clinic to which they referred (8.7 ± 8.0 vs. 13.4 ± 11.6 vs. 19.8 ± 8.7 vs. 7.4 ± 8.1 for endocrine, diabetic, rheumatologic, and gastroenterological diseases, respectively, p <.001). Conclusions: We described a large series of patients affected by APS according to splitters and lumpers. We propose a flowchart tailored for each specialist outpatient clinic taking care of the patients. Finally, we recommend regular reproductive system assessment due to the non-negligible risk of developing premature ovarian failure
Submicron Structures Technology and Research
Contains reports on ten research projects.Joint Services Electronics Program (Contract DAAG29-83-K-0003)Joint Services Electronics Program (Contract DAAL03-86-K-0002)National Science Foundation (Grant ECS82-05701)National Science Foundation (Grant ECS85-06565)Lawrence Livermore Laboratory (Subcontract 2069209)National Science Foundation (Grant ECS85-03443)U.S. Air Force - Office of Scientific Research (Grant AFOSR-85-0154)National Aeronautics and Space Administration (Grant NGL22-009-638)National Science Foundation (through KMS Fusion, Inc.)U.S. Navy - Office of Naval Research (Contract N00014-79-C-0908
Submicron Structures Technology and Research
Contains reports on fourteen research projects.Joint Services Electronics Program (Contract DAAG29-83-K-0003)U.S. Navy - Office of Naval Research (Contract N00014-79-C-0908)National Science Foundation (Grant ECS82-05701)Semiconductor Research Corporation (Grant 83-01-033)U.S. Department of Energy (Contract DE-ACO2-82-ER-13019)Lawrence Livermore National Laboratory (Contract 2069209)National Aeronautics and Space Administration (Contract NAS5-27591)Defense Advanced Research Projects Agency (Contract N00014-79-C-0908)National Science Foundation (Grant ECS80-17705)National Aeronautics and Space Administration (Contract NGL22-009-638
Submicron Structures Technology and Research
Contains reports on fifteen research projects.Joint Services Electronics Program (Contract DAALO3-86-K-0002)National Science Foundation (Grant ECS 87-09806)Semiconductor Research Corporation (Contract 87-SP-080)National Science Foundation (Grant ECS 85-03443)U.S. Air Force - Office of Scientific Research (Grant AFOSR 85-0376)National Science Foundation (Grant ECS 85-06565)U.S. Air Force - Office of Scientific Research (Grant AFOSR 85-0154)Lawrence Livermore National Laboratory (Subcontract 2069209)National Aeronautics and Space Adminstration (Grant NGL22-009-683)Collaboration with KMS Fusion, Inc
Oxidation of benzoin catalyzed by oxovanadium (IV) schiff base complexes
BACKGROUND: The oxidative transformation of benzoin to benzil has been accomplished by the use of a wide
variety of reagents or catalysts and different reaction procedures. The conventional oxidizing agents yielded mainly
benzaldehyde or/and benzoic acid and only a trace amount of benzil. The limits of practical utilization of these
reagents involves the use of stoichiometric amounts of corrosive acids or toxic metallic reagents, which in turn
produce undesirable waste materials and required high reaction temperatures.
In recent years, vanadium complexes have attracted much attention for their potential utility as catalysts for various
types of reactions.
RESULTS: Active and selective catalytic systems of new unsymmetrical oxovanadium(IV) Schiff base complexes for
the oxidation of benzoin is reported. The Schiff base ligands are derived between 2-aminoethanol and 2-hydroxy-1-
naphthaldehyde (H2L1) or 3-ethoxy salicylaldehyde (H2L3); and 2-aminophenol and 3-ethoxysalicylaldehyde (H2L2) or
2-hydroxy-1-naphthaldehyde (H2L4). The unsymmetrical Schiff bases behave as tridentate dibasic ONO donor
ligands. Reaction of these Schiff base ligands with oxovanadyl sulphate afforded the mononuclear oxovanadium(IV)
complexes (VIVOLx.H2O), which are characterized by various physico-chemical techniques.
The catalytic oxidation activities of these complexes for benzoin were evaluated using H2O2 as an oxidant. The best
reaction conditions are obtained by considering the effect of solvent, reaction time and temperature. Under the
optimized reaction conditions, VOL4 catalyst showed high conversion (>99%) with excellent selectivity to benzil
(~100%) in a shorter reaction time compared to the other catalysts considered.
CONCLUSION: Four tridentate ONO type Schiff base ligands were synthesized. Complexation of these ligands with
vanadyl(IV) sulphate leads to the formation of new oxovanadium(IV) complexes of type VIVOL.H2O.
Elemental analyses and spectral data of the free ligands and their oxovanadium(IV) complexes were found to be in
good agreement with their structures, indicating high purity of all the compounds.
Oxovanadium complexes were screened for the oxidation of benzoin to benzil using H2O2 as oxidant. The effect of
time, solvent and temperature were optimized to obtain maximum yield. The catalytic activity results demonstrate
that these catalytic systems are both highly active and selective for the oxidation of benzoin under mild reaction
conditions.Web of Scienc
Submicron Structures Technology and Research
Contains table of contents for Part I, table of contents for Section 1 and reports on fourteen research projects.Joint Services Electronics Program (Contract DAAL03-86-K-0002)Joint Services Electronics Program (Contract DAAL03-89-C-0001)National Science Foundation (Grant ECS-87-09806)Semiconductor Research Corporation (Contract 87-SP-080)Hampshire Instruments CorporationNational Science Foundation (Grant ECS-85-03443)U.S. Air Force - Office of Scientific Research (Grant AFOSR-88-0304)National Science Foundation (Grant ECS-85-06565)X-Opt., IncorporatedU.S. Air Force - Office of Scientific Research (Grant AFOSR-85-0154)National Aeronautics and Space Administration (Grant NGL22-009-683)KMS Fusion, Incorporate
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