Evaluation of microbial adjuncts and their effect on the ripening of cheddar cheese

A bacteriocin-producing strain of Lactobacillus paracasei DPC 4715 was used as an adjunct culture in Cheddar cheese in order to control the growth of “wild” nonstarter lactic acid bacteria. No suppression of growth of the indicator strain was observed in the experimental cheese. The bacteriocin produced by Lactobacillus paracasei DPC 4715 was sensitive to chymosin and cathepsin D and it may have been cleaved by the rennet used for the cheese manufactured or by indigenous milk proteases. A series of studies were performed using various microbial adjuncts to influence cheese ripening. Microbacterium casei DPC 5281, Corynebacterium casei DPC 5293 and Corynebacterium variabile DPC 5305 were added to the cheesemilk at level of 109 cfu/ml resulting in a final concentration of 108 cfu/g in Cheddar cheese. The strains significantly increased the level of pH 4.6-soluble nitrogen, total free amino acids after 60 and 180 d of ripening and some individual free amino acids after 180 d. Yarrowia lipolytica DPC 6266, Yarrowia lipolytica DPC 6268 and Candida intermedia DPC 6271 were used to accelerate the ripening of Cheddar cheese. Strains were grown in YG broth to a final concentration of 107 cfu/ml, microfluidized, freeze-dried and added to the curd during salting at level of 2% w/w. The yeasts positively affected the primary, secondary proteolysis and lipolysis of cheeses and had aminopeptidase, dipeptidase, esterase and 5’ phosphodiestere activities that contributed to accelerate the ripening and improve the flavor of cheese. Hafia alvei was added to Cheddar cheesemilk at levels of 107 cfu/ml and 108 cfu/ml and its contribution during ripening was evaluated. The strain significantly increased the level of pH 4.6-soluble nitrogen, total free amino-acids, and some individual free amino-acids of Cheddar cheese, whereas no differences in the urea-polyacrylamide gel electrophoresis (urea-PAGE) electrophoretograms of the cheeses were detected. Hafia alvei also significantly increased the level of some biogenic amines. A low-fat Cheddar cheese was made with Bifidobacterium animalis subsp. lactis, strain BB-12® at level of 108 cfu/ml, as a probiotic adjunct culture and Hi-Maize® 260 (resistant high amylose maize starch) at level of 2% and 4% w/v, as a prebiotic fiber which also played the role of fat replacer. Bifidobacterium BB-12 decreased by 1 log cycle after 60 d of ripening and remained steady at level of ~107 cfu/g during ripening. The Young’s modulus also increased proportionally with increasing levels of Hi-maize. Hencky strain at fracture decreased over ripening and increased with increasing in fat replacer. A cheese based medium (CBM) was developed with the purpose of mimicking the cheese environment at an early ripening stage. The strains grown in CBM showed aminopeptidase activity against Gly-, Arg-, Pro- and Phe-p-nitroanalide, whereas, when grown in MRS they were active against all the substrates tested. Both Lb. danicus strains grown in MRS and in CBM had aminotransferase activity towards aromatic amino acids (Phe and Trp) and also branched-chain amino acids (Leu and Val). Esterase activity was expressed against p-nitrophenyl-acetate (C2), pnitrophenyl- butyrate (C4) and p-nitrophenyl-palmitate (C16) and was significantly higher in CBM than in MRS.

The synchronization of superparamagnetic beads driven by a micro-magnetic ratchet.

We present theoretical, numerical, and experimental analyses on the non-linear dynamic behavior of superparamagnetic beads exposed to a periodic array of micro-magnets and an external rotating field. The agreement between theoretical and experimental results revealed that non-linear magnetic forcing dynamics are responsible for transitions between phase-locked orbits, sub-harmonic orbits, and closed orbits, representing different mobility regimes of colloidal beads. These results suggest that the non-linear behavior can be exploited to construct a novel colloidal separation device that can achieve effectively infinite separation resolution for different types of beads, by exploiting minor differences in their bead's properties. We also identify a unique set of initial conditions, which we denote the "devil's gate" which can be used to expeditiously identify the full range of mobility for a given bead type.

Correlates of HIV testing among abused women in South Africa.

Gender-based violence increases a woman's risk for HIV but little is known about her decision to get tested. We interviewed 97 women seeking abuse-related services from a nongovernmental organization (NGO) in Johannesburg, South Africa. Forty-six women (47%) had been tested for HIV. Caring for children (odds ratio [OR] = 0.27, 95% confidence interval [CI] = [0.07, 1.00]) and conversing with partner about HIV (OR = 0.13, 95% CI = [0.02, 0.85]) decreased odds of testing. Stronger risk-reduction intentions (OR = 1.27, 95% CI = [1.01, 1.60]) and seeking help from police (OR = 5.51, 95% CI = [1.18, 25.76]) increased odds of testing. Providing safe access to integrated services and testing may increase testing in this population. Infection with HIV is highly prevalent in South Africa where an estimated 16.2% of adults between the ages of 15 and 49 have the virus. The necessary first step to stemming the spread of HIV and receiving life-saving treatment is learning one's HIV serostatus through testing. Many factors may contribute to someone's risk of HIV infection and many barriers may prevent testing. One factor that does both is gender-based violence.

Magnetophoretic circuits for digital control of single particles and cells.

The ability to manipulate small fluid droplets, colloidal particles and single cells with the precision and parallelization of modern-day computer hardware has profound applications for biochemical detection, gene sequencing, chemical synthesis and highly parallel analysis of single cells. Drawing inspiration from general circuit theory and magnetic bubble technology, here we demonstrate a class of integrated circuits for executing sequential and parallel, timed operations on an ensemble of single particles and cells. The integrated circuits are constructed from lithographically defined, overlaid patterns of magnetic film and current lines. The magnetic patterns passively control particles similar to electrical conductors, diodes and capacitors. The current lines actively switch particles between different tracks similar to gated electrical transistors. When combined into arrays and driven by a rotating magnetic field clock, these integrated circuits have general multiplexing properties and enable the precise control of magnetizable objects.

Nurse-led behavioral management of diabetes and hypertension in community practices: a randomized trial.

BACKGROUND: Several trials have demonstrated the efficacy of nurse telephone case management for diabetes (DM) and hypertension (HTN) in academic or vertically integrated systems. Little is known about the real-world potency of these interventions. OBJECTIVE: To assess the effectiveness of nurse behavioral management of DM and HTN in community practices among patients with both diseases. DESIGN: The study was designed as a patient-level randomized controlled trial. PARTICIPANTS: Participants included adult patients with both type 2 DM and HTN who were receiving care at one of nine community fee-for-service practices. Subjects were required to have inadequately controlled DM (hemoglobin A1c [A1c] ≥ 7.5%) but could have well-controlled HTN. INTERVENTIONS: All patients received a call from a nurse experienced in DM and HTN management once every two months over a period of two years, for a total of 12 calls. Intervention patients received tailored DM- and HTN- focused behavioral content; control patients received non-tailored, non-interactive information regarding health issues unrelated to DM and HTN (e.g., skin cancer prevention). MAIN OUTCOMES AND MEASURES: Systolic blood pressure (SBP) and A1c were co-primary outcomes, measured at 6, 12, and 24 months; 24 months was the primary time point. RESULTS: Three hundred seventy-seven subjects were enrolled; 193 were randomized to intervention, 184 to control. Subjects were 55% female and 50% white; the mean baseline A1c was 9.1% (SD = 1%) and mean SBP was 142 mmHg (SD = 20). Eighty-two percent of scheduled interviews were conducted; 69% of intervention patients and 70% of control patients reached the 24-month time point. Expressing model estimated differences as (intervention--control), at 24 months, intervention patients had similar A1c [diff = 0.1 %, 95 % CI (-0.3, 0.5), p = 0.51] and SBP [diff = -0.9 mmHg, 95% CI (-5.4, 3.5), p = 0.68] values compared to control patients. Likewise, DBP (diff = 0.4 mmHg, p = 0.76), weight (diff = 0.3 kg, p = 0.80), and physical activity levels (diff = 153 MET-min/week, p = 0.41) were similar between control and intervention patients. Results were also similar at the 6- and 12-month time points. CONCLUSIONS: In nine community fee-for-service practices, telephonic nurse case management did not lead to improvement in A1c or SBP. Gains seen in telephonic behavioral self-management interventions in optimal settings may not translate to the wider range of primary care settings.

SCHUBERT’S WINTERREISE AND THE PIANO TRIO IN Eb; TWO REMARKABLE WORKS FROM ONE REMARKABLE YEAR – 1827: A RECORDING PROJECT

During Franz Schubert’s penultimate year of 1827, he produced two profoundly important and mature works that are the focus of this recording project. The works are, in chronological order: • Winterreise (cycle of 24 songs on the poetry of Wilhelm Müller, 1794-1827) • Piano Trio in Eb Major, Op. 100, D. 929 A unique feature of the project is to present Winterreise in two poetic orders: as traditionally performed and published by Schubert, and in the final ordering published by the poet. The program notes accompanying the dissertation’s three compact discs have extensive information as well as comparative tables of Müller’s and Schubert’s final ordering of the cycle. There are significant differences in ordering, and ultimately the listener will determine which is more dramatically satisfying. Dark melancholy is the central emotion in Winterreise, which Schubert composed at various times throughout 1827 in a mood of corresponding gloom and distress. By contrast, the summer and fall of that year produced, in quick succession, the two glowing and remarkable Piano Trios in Bb and Eb, the second of which is included on these compact discs. The contrast between the trios and Winterreise follows the outward circumstances of Schubert’s life and health, a pattern of sorrow and later consolation and elation. The sound recordings for this dissertation recording project are available on three compact discs that can be found in the Digital Repository at the University of Maryland (DRUM). Winterreise was recorded in August 2009, at the University of Baltimore recital hall in Baltimore, Maryland with University of Maryland Professor François Loup. The trio, recorded in live performance in Baltimore in the spring of 2010, features two members of the Baltimore Symphony Orchestra: Qing Li, B.S.O. principal second violin, and Bo Li, B.S.O. section cellist.

Bridging the Divide Between the Soloist and the Ensemble Player

In conservatories and music schools, the general practice for an aspiring pianist is to focus on solo performance learning mainly solo repertoire. With the advent of the advanced degree in collaborative piano, pianists could submerge themselves in the study of duo sonatas, larger chamber music ensembles, and art song. The appearance of this degree was an important step in the development of pianists, as this kind of work requires specific training and focus to master the vast repertoire involved. However it also more clearly brought out the invisible divide separating the solo pianist from the collaborative pianist, a.k.a. the accompanist. While geniuses such as Bach, Beethoven and Brahms were known to compose and perform all types of music, the appearance of super stars such as Liszt and Paganini helped bring into being the term accompanist and since then music world has tacitly embraced this divide. The goal of my dissertational study is to show that this divide need not exist. The three recitals which comprise this dissertational project were all performed at the University of Maryland, the first on 12 November 2010 at Gildenhom Recital Hall, the second at Ulrich Recital Hall on 10 September 2011, and the third at Gildenhorn Recital Hall on 11 November 2011. The repertoire included Rachmaninoff Prelude in g# minor op. 32 no. 12 and Etude-Tableaux in Eb minor op. 29 no. 5, Brahms Sonata for Piano and Violin in d minor op. 108, Mendelssohn Piano Trio in d minor op. 49, Chopin Sonata No.2 in Bb minor, Franck Sonata for Piano and Violin, Prokofiev Piano Concerto no. 2 in g minor op. 16 with pianist Elizabeth Brown as orchestra, Beethoven Sonata for Piano and Violin in A op 47 (Kreutzer), and Paul Schoenfield Cafe Music. All works with violin and cello were performed with violinist Rebecca Racusin, and cellist Devree Lewis. The recitals were recorded on compact discs and are archived within the Digital Repository at the University of Maryland(DRUM).

Characterizing the Switching Thresholds of Magnetophoretic Transistors.

The switching thresholds of magnetophoretic transistors for sorting cells in microfluidic environments are characterized. The transistor operating conditions require short 20-30 mA pulses of electrical current. By demonstrating both attractive and repulsive transistor modes, a single transistor architecture is used to implement the full write cycle for importing and exporting single cells in specified array sites.