11,651 research outputs found
Development of a Tabletop Soft Gel Encapsulation Machine
Currently, to test new formulations of gel capsules at Pfizer, they must use the large-scale machine that requires a minimum of 25 kg of gel melt and produce hundreds of capsules per run. Production at a smaller scale to enable rapid changeover for research and development is desired. The team’s goal was to achieve continuous production of sealed capsules with 80% fill capacity. Capsule sealing was the prime consideration. Preliminary trials using the existing system and heat transfer analysis indicated localized heating was necessary to promote capsule sealing. To provide localized heating, a brass wedge was designed based on the pilot scale machine. The machined wedge was integrated with a PID control system. Using pre-made gelatin ribbons, the appropriate process parameters to achieve sealed capsules were determined. The critical, coupled parameters were die roll temperature, wedge temperature, wedge height, and die roll speed. Capsule sealing efficiency was highest at a speed of 4 capsules/min. For air-filled capsules, a sealing efficiency of 100% was achieved. For PEG-400-filled capsules, a sealing efficiency of 50% was achieved. Future work will include integration with the gelatin feed system and addition of a vacuum during capsule formation to increase fill capacity.https://scholarscompass.vcu.edu/capstone/1151/thumbnail.jp
Spectral projections and resolvent bounds for partially elliptic quadratic differential operators
We study resolvents and spectral projections for quadratic differential
operators under an assumption of partial ellipticity. We establish
exponential-type resolvent bounds for these operators, including
Kramers-Fokker-Planck operators with quadratic potentials. For the norms of
spectral projections for these operators, we obtain complete asymptotic
expansions in dimension one, and for arbitrary dimension, we obtain exponential
upper bounds and the rate of exponential growth in a generic situation. We
furthermore obtain a complete characterization of those operators with
orthogonal spectral projections onto the ground state.Comment: 60 pages, 3 figures. J. Pseudo-Differ. Oper. Appl., to appear.
Revised according to referee report, including minor changes to Corollary
1.8. The final publication will be available at link.springer.co
Latent tuberculosis infection screening and treatment in HIV: insights from evaluation of UK practice
Latent TB infection (LTBI) screening and treatment in HIV-positive individuals in the UK is advocated by the British HIV Association (BHIVA) and National Institute for Health and Care Excellence (NICE), although each recommends differing strategies. We undertook an evaluation of UK practice, relating the responses to the local HIV/TB disease burden. 162 of 188 (86%) UK geographical areas responded; only 93/162 (57.4%) offer LTBI testing with considerable heterogeneity in practice, and no difference in HIV/TB burden between areas offering testing and those who do not. Only 33/93 (35.5%) and 6/93 (6.5%) reported full compliance with BHIVA and NICE guidance respectively. A uniform national guideline is required
Thermodynamics of an ideal generalized gas:II Means of order
The property that power means are monotonically increasing functions of their
order is shown to be the basis of the second laws not only for processes
involving heat conduction but also for processes involving deformations. In an
-potentail equilibration the final state will be one of maximum entropy,
while in an entropy equilibrium the final state will be one of minimum . A
metric space is connected with the power means, and the distance between means
of different order is related to the Carnot efficiency. In the ideal classical
gas limit, the average change in the entropy is shown to be proportional to the
difference between the Shannon and R\'enyi entropies for nonextensive systems
that are multifractal in nature. The -potential, like the internal energy,
is a Schur convex function of the empirical temperature, which satisfies
Jensen's inequality, and serves as a measure of the tendency to uniformity in
processes involving pure thermal conduction.Comment: 8 page
Using baryon octet magnetic moments and masses to fix the pion cloud contribution
Using SU(3) symmetry to constrain the pion BB' couplings, assuming SU(3)
breaking comes only from one-loop pion cloud contributions, and using the the
covariant spectator theory to describe the photon coupling to the quark core,
we show how the experimental masses and magnetic moments of the baryon octet
can be used to set a model independent constraint on the strength of the pion
cloud contributions to the octet, and hence the nucleon, form factors at Q2=0.Comment: 7 pages, 1 figur
Extrapontine myelinolysis presenting as acute parkinsonism
BACKGROUND: Extrapontine myelinolysis presenting with extra pyramidal features suggestive of parkinsonism may be a challenging clinical syndrome. Clinicians should maintain their vigilance while correcting electrolyte imbalances, especially with associated co-morbidity. CASE PRESENTATION: A 41-year-old woman presented with acute parkinsonism like features while on a holiday. This followed slow correction of hyponatraemia after repeated vomiting. MRI changes were suggestive of Extrapontine myelinolysis(EPM). This case is at variance with four previous cases reported in the medical literature in that the patient made a full clinical recovery and the MR changes resolved with symptomatic support alone. CONCLUSION: Extrapontine myelinolysis could make a complete recovery with symptomatic support alone. During hyponatraemia correction, rapid osmotic shifts of fluid that cause hypernatremia, causes myelinolysis rather than absolute serum sodium level. Even gradual correction of hyponatraemia can produce myelinolysis, especially with pre-existing malnourishment, alcoholism, drug misuse, Addison's disease and immuno-suppression. Pallidial sparing is typical of EPM in MRI scans
Finding what works: Identification of implementation strategies for the integration of methadone maintenance therapy and HIV services in Vietnam
Abstract Background Integration of methadone maintenance therapy (MMT) and HIV services is an evidence-based intervention (EBI) that benefits HIV care and reduces costs. While MMT/HIV integration is recommended by the World Health Organization and the Centers for Disease Control and Prevention, it is not widely implemented, due to organizational and operational barriers. Our study applied an innovative process to identify implementation strategies to address these barriers. Methods Our process was adapted from the Expert Recommendations for Implementing Change (ERIC) protocol and consisted of two main phases. In Phase 1, we conducted 16 in-depth interviews with stakeholders and developed matrices to display barriers to integration. In Phase 2, we selected implementation strategies that addressed the barriers identified in Phase 1 and conducted a poll to vote on the most important and feasible strategies among a panel with expertise in cultural context and implementation science. Results Barriers fell into two broad categories: policy and programmatic. At the policy level, barriers included lack of a national mandate, different structures (MMT vs. HIV clinic) for cost reimbursement and staff salaries, and resistance on the part of staff to take on additional tasks without compensation. Programmatic barriers included the need for cross-training in MMT and HIV tasks, staff accountability, and commitment from local leaders. In Phase 2, we focused on programmatic challenges. Based on voting results and iterative dialogue with our expert panel, we selected several implementation strategies in the domains of technical assistance, staff accountability, and local commitment that targeted these barriers. Conclusions Key programmatic barriers to MMT/HIV integration in Vietnam may be addressed through implementation strategies that focus on technical assistance, staff accountability, and local commitment. Our process of identifying implementation strategies was simple, low cost, and potentially replicable to other settings
PCBs Exert an Estrogenic Effect through Repression of the Wnt7a Signaling Pathway in the Female Reproductive Tract
Polychlorinated biphenyls (PCBs) have been proposed to have a weak estrogenic activity and therefore pose a risk as potential environmental endocrine disruptors to the perinatal development of the female reproductive tract. Perinatal exposure to high concentrations of the potent synthetic estrogen diethylstilbestrol (DES) induces abnormal development of the female reproductive tract via a mechanism that acts through the down-regulation of Wnt7a (wingless-type MMTV integration site family, member 7A). To test the hypothesis that PCBs act as weak estrogens, we injected neonatal mice with a commercial PCB mixture (Aroclor 1254) or with low levels of DES and measured effects of exposure on Wnt7a expression and uterine morphology. We report here that neonatal PCB or low-level DES exposure resulted in the down-regulation of Wnt7a expression. In addition, both PCB and low-level DES exposure induced changes in the uterine myometrium and gland formation. These data reveal that weak estrogens such as the PCBs act through a Wnt7a-dependent pathway and suggest that Wnt7a regulation is a sensitive biomarker for testing weak estrogenic candidate compounds. The morphologic changes that were elicited by PCBs and DES were different immediately after exposure, suggesting that Wnt7a-independent pathways are also activated by one or both of these compounds. Although Wnt7a down-regulation is transient after estrogenic exposure, subsequent morphologic changes became more pronounced during postnatal and adult life, suggesting that the female reproductive tract is permanently reprogrammed after exposure even to weak estrogenic compounds. In addition, Wnt7a heterozygous mice were more sensitive to PCB exposure, revealing an important genetic predisposition to risks of environmental endocrine disruptors
Exploring OER strategies to enable the recasting of the core graduate library management course
At a recent administrative library council meeting of an urban university, a representative from that system's graduate program in library and information science indicated that the library management course could be refreshed. They asked how the campus library leaders could assist in updating that curriculum. Inspired by the vibrant activity of the Open Educational Recourses (OER) maelstrom across that university, it was suggested that the ailing management course could be updated with refreshed, current management concerns and delivered in an up-to-date and flexible OER package. The panel consisting of LIS educators and practitioners will discuss how this could be accomplished
A NICER Discovery of a Low-Frequency Quasi-Periodic Oscillation in the Soft-Intermediate State of MAXI J1535-571
We present the discovery of a low-frequency Hz quasi-periodic
oscillation (QPO) feature in observations of the black hole X-ray binary MAXI
J1535-571 in its soft-intermediate state, obtained in September-October 2017 by
the Neutron Star Interior Composition Explorer (NICER). The feature is
relatively broad (compared to other low-frequency QPOs; quality factor
) and weak (1.9% rms in 3-10 keV), and is accompanied by a weak
harmonic and low-amplitude broadband noise. These characteristics identify it
as a weak Type A/B QPO, similar to ones previously identified in the
soft-intermediate state of the transient black hole X-ray binary XTE J1550-564.
The lag-energy spectrum of the QPO shows increasing soft lags towards lower
energies, approaching 50 ms at 1 keV (with respect to a 3-10 keV continuum).
This large phase shift has similar amplitude but opposite sign to that seen in
Rossi X-ray Timing Explorer data for a Type B QPO from the transient black hole
X-ray binary GX 339-4. Previous phase-resolved spectroscopy analysis of the
Type B QPO in GX 339-4 pointed towards a precessing jet-like corona
illuminating the accretion disk as the origin of the QPO signal. We suggest
that this QPO in MAXI J1535-571 may have the same origin, with the different
lag sign depending on the scale height of the emitting region and the observer
inclination angle.Comment: Accepted for publication in ApJ Letter
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