Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Reading LevelReading Level
-
Content TypeContent Type
-
YearFrom:-To:
-
More FiltersMore FiltersItem TypeIs Full-Text AvailableSubjectPublisherSourceDonorLanguagePlace of PublicationContributorsLocation
Done
Filters
Reset
484
result(s) for
"MacDonald, Eric"
Sort by:
The Program : lessons from elite military units for creating and sustaining high performance leaders and teams
\"The Program, a successful team-building and leadership company, has been helping develop better leaders and build cohesive teams for over a decade....This practical, hands-on guide helps you understand and implement the tactics and techniques of a Championship Culture, such as accountability, commitment, and communication - underscored by personal stories of actual combat situations. Designed to be used as a blueprint for developing highly motivated teams and teadm leaders, this book lays out a tried-and-tested plan to achieve exemplary results in organizations of any type apd size. Offering unforgettable illustrative examples, practical guidance, and real-world advice, The Program is a must-have resource for teams and leaders at all levels.\" -- back cover.
Multiprocess 3D printing for increasing component functionality
2016
Layer-by-layer deposition of materials to manufacture parts—better known as three-dimensional (3D) printing or additive manufacturing—has been flourishing as a fabrication process in the past several years and now can create complex geometries for use as models, assembly fixtures, and production molds. Increasing interest has focused on the use of this technology for direct manufacturing of production parts; however, it remains generally limited to single-material fabrication, which can limit the end-use functionality of the fabricated structures. The next generation of 3D printing will entail not only the integration of dissimilar materials but the embedding of active components in order to deliver functionality that was not possible previously. Examples could include arbitrarily shaped electronics with integrated microfluidic thermal management and intelligent prostheses custom-fit to the anatomy of a specific patient. We review the state of the art in multiprocess (or hybrid) 3D printing, in which complementary processes, both novel and traditional, are combined to advance the future of manufacturing.
Journal Article
Stress-mediating inflammatory cytokine profiling reveals unique patterns in malaria and typhoid fever patients
by
Kamdem, Severin Donald
,
Nji, Akindeh Mbu
,
Mbacham, Wilfred Fon
in
Adolescent
,
Adult
,
Antigens
2025
Malaria and typhoid fever pose significant health risks, leading to severe morbidity and mortality when inadequately treated. Understanding the role of stress-related inflammatory cytokines is crucial, as they mediate immune responses that affect pathogen clearance and recovery. This study investigated the cytokine profiles in patients with malaria and/or typhoid fever attending the Obala District Hospital in Yaoundé, Cameroon. We conducted a cross-sectional observational study measuring cortisol and inflammatory cytokines in blood samples from 55 infected patients and a control group of 15 healthy individuals using ELISA kits. We also evaluated psychological stress over the past 30 days using a 10-item Perceived Stress Scale (PSS) questionnaire to explore the link between stress and immune response. Psychological stress levels were notably higher in the typhoid fever group (18.20 ± 5.5) compared to the other groups, although these differences were statistically insignificant. Cortisol levels were significantly elevated (p < 0.001) across all patient groups compared to controls, with the typho-malaria group demonstrating a 2.5-fold increase. Notably, cytokine levels were elevated in patients with malaria and typhoid comorbidity, particularly IL-1β, IL-2, TNF-α, and IFN-γ. While IL-6 concentrations were significantly higher in malaria and typho-malaria co-infected patients, IL-10 levels were reduced in the typho-malaria group but remained elevated compared to controls. The TNF-α/IL-10 ratio was significantly higher in the co-infected group, suggesting a heightened inflammatory response. Additionally, there was a positive correlation between perceived stress scores and IL-2 (r = 0.365, p = 0.002), IFN-γ (r = 0.248, p = 0.03), and IL-6 (r = 0.412, p = 0.0001) in the typho-malaria group. Beyond IL-6, no significant correlations were observed between stress indices and the anti-inflammatory cytokines IL-4 (r = 0.204, p = 0.09) and IL-10 (r = 0.153, p = 0.20) among co-infected individuals. These results suggest that stress response may play a crucial role in shaping the inflammatory landscape during malaria and typhoid fever. Exposure to severe stressors may disrupt immune response and contribute to negative health outcomes. Understanding the immunopathogenesis of these diseases could potentially pave the way for the development of novel therapeutic strategies targeting the stress-cytokine axis.
Journal Article
Integrating stereolithography and direct print technologies for 3D structural electronics fabrication
2012
Purpose - The purpose of this paper is to present a hybrid manufacturing system that integrates stereolithography (SL) and direct print (DP) technologies to fabricate three-dimensional (3D) structures with embedded electronic circuits. A detailed process was developed that enables fabrication of monolithic 3D packages with electronics without removal from the hybrid SL DP machine during the process. Successful devices are demonstrated consisting of simple 555 timer circuits designed and fabricated in 2D (single layer of routing) and 3D (multiple layers of routing and component placement).Design methodology approach - A hybrid SL DP system was designed and developed using a 3D Systems SL 250 50 machine and an nScrypt micro-dispensing pump integrated within the SL machine through orthogonally-aligned linear translation stages. A corresponding manufacturing process was also developed using this system to fabricate 2D and 3D monolithic structures with embedded electronic circuits. The process involved part design, process planning, integrated manufacturing (including multiple starts and stops of both SL and DP and multiple intermediate processes), and post-processing. SL provided substrate mechanical structure manufacturing while interconnections were achieved using DP of conductive inks. Simple functional demonstrations involving 2D and 3D circuit designs were accomplished.Findings - The 3D micro-dispensing DP system provided control over conductive trace deposition and combined with the manufacturing flexibility of the SL machine enabled the fabrication of monolithic 3D electronic structures. To fabricate a 3D electronic device within the hybrid SL DP machine, a process was developed that required multiple starts and stops of the SL process, removal of uncured resin from the SL substrate, insertion of active and passive electronic components, and DP and laser curing of the conductive traces. Using this process, the hybrid SL DP technology was capable of successfully fabricating, without removal from the machine during fabrication, functional 2D and 3D 555 timer circuits packaged within SL substrates.Research limitations implications - Results indicated that fabrication of 3D embedded electronic systems is possible using the hybrid SL DP machine. A complete manufacturing process was developed to fabricate complex, monolithic 3D structures with electronics in a single set-up, advancing the capabilities of additive manufacturing (AM) technologies. Although the process does not require removal of the structure from the machine during fabrication, many of the current sub-processes are manual. As a result, further research and development on automation and optimization of many of the sub-processes are required to enhance the overall manufacturing process.Practical implications - A new methodology is presented for manufacturing non-traditional electronic systems in arbitrary form, while achieving miniaturization and enabling rugged structure. Advanced applications are demonstrated using a semi-automated approach to SL DP integration. Opportunities exist to fully automate the hybrid SL DP machine and optimize the manufacturing process for enhancing the commercial appeal for fabricating complex systems.Originality value - This work broadly demonstrates what can be achieved by integrating multiple AM technologies together for fabricating unique devices and more specifically demonstrates a hybrid SL DP machine that can produce 3D monolithic structures with embedded electronics and printed interconnects.
Journal Article
Immune cell profiles of patients with interstitial cystitis/bladder pain syndrome
by
Tabansky, Inna
,
Ruzimovsky, Marina
,
Miller, Edmund J.
in
Biomedical and Life Sciences
,
Biomedicine
,
Development and progression
2022
Interstitial cystitis/bladder pain syndrome (IC/BPS) is a disorder characterized by bladder pain upon filling which severely affects quality of life. Clinical presentation can vary. Local inflammatory events typify the clinical presentation of IC/BPS patients with Hunner lesions (IC/BPS-HL). It has previously been proposed that B cells are more prevalent in HL, but understanding their exact role in this environment requires a more complete immunological profile of HL. We characterized immunological dysfunction specifically in HL using immunohistochemistry. We detected significantly more plasma cells (50× increase, p < 0.0001), B cells (28× increase, p < 0.0001), T cells (3× increase, p < 0.0001), monocytes/macrophages (6× increase, p < 0.0001), granulocytes (4× increase, p < 0.0001), and natural killer cells (2× increase, p = 0.0249) in IC/BPS patients with HL than in unaffected controls (UC). Patients with IC/BPS-HL also had significantly elevated urinary levels of IL-6 (p = 0.0054), TNF-α (p = 0.0064) and IL-13 (p = 0.0304) compared to patients with IC/BPS without HL (IC/BPS-NHL). In contrast, IL-12p70 levels were significantly lower in the patients with HL than in those without these lesions (p = 0.0422). Different cytokines were elevated in the urine of IC/BPS patients with and without HL, indicating that different disease processes are active in IC/BPS patients with and without HL. Elevated levels of CD138+, CD20+, and CD3+ cells in HL are consistent B and T-cell involvement in disease processes within HL.
Journal Article
Exploring the relationship between socioeconomic status and erectile dysfunction: an analysis of the National Health and Nutrition Examination Survey
2023
The aim of this study was to investigate the association between socioeconomic status and erectile dysfunction. Data were obtained from the National Health and Nutrition Examination Survey, a nationally representative survey of the United States population. Socioeconomic status was estimated using the poverty income ratio, a ratio of family income to established poverty levels. Erectile function was assessed from a single survey question and was divided into two groups: normal (always and usually able to maintain an erection) and erectile dysfunction (sometimes or never able to maintain an erection). Multivariable logistic regression, using a multi-model approach, was used to characterize the interplay between well-established risk factors for erectile dysfunction and socioeconomic status. Our final cohort included 3679 respondents, representative of 81,255,155 subjects with a mean age of 44.4 [SE, 0.365]. Multivariable logistic regression showed that low-income respondents were significantly more likely to report erectile dysfunction [adjusted odds ratio (AOR) = 1.95, 95% CI 1.28–2.96;
p
= 0.003] compared to higher-income respondents. This study suggests that low socioeconomic status may be associated with erectile dysfunction in a large, nationally representative sample.
Journal Article
3D Printed Shape Memory Polymers Produced via Direct Pellet Extrusion
by
Cersoli, Trenton
,
MacDonald, Eric
,
Herberger, Callan
in
3-D printers
,
3D printing shape memory polymers
,
actuation
2021
Shape memory polymers (SMPs) are materials capable of changing their structural configuration from a fixed shape to a temporary shape, and vice versa when subjected to a thermal stimulus. The present work has investigated the 3D printing process of a shape memory polymer (SMP)-based polyurethane using a material extrusion technology. Here, SMP pellets were fed into a printing unit, and actuating coupons were manufactured. In contrast to the conventional film-casting manufacturing processes of SMPs, the use of 3D printing allows the production of complex parts for smart electronics and morphing structures. In the present work, the memory performance of the actuating structure was investigated, and their fundamental recovery and mechanical properties were characterized. The preliminary results show that the assembled structures were able to recover their original conformation following a thermal input. The printed parts were also stamped with a QR code on the surface to include an unclonable pattern for addressing counterfeit features. The stamped coupons were subjected to a deformation-recovery shape process, and it was observed that the QR code was recognized after the parts returned to their original shape. The combination of shape memory effect with authentication features allows for a new dimension of counterfeit thwarting. The 3D-printed SMP parts in this work were also combined with shape memory alloys to create a smart actuator to act as a two-way switch to control data collection of a microcontroller.
Journal Article
Novel ABS-based binary and ternary polymer blends for material extrusion 3D printing
by
MacDonald, Eric
,
Roberson, David A.
,
Torrado Perez, Angel R.
in
3-D printers
,
ABS resins
,
Acrylonitrile butadiene styrene
2014
Material extrusion 3D printing (ME3DP) based on fused deposition modeling (FDM) technology is currently the most commonly used additive manufacturing method. However, ME3DP suffers from a limitation of compatible materials and typically relies upon amorphous thermoplastics, such as acrylonitrile butadiene styrene (ABS). The work presented here demonstrates the development and implementation of binary and ternary polymeric blends for ME3DP. Multiple blends of acrylonitrile butadiene styrene (ABS), styrene ethylene butadiene styrene (SEBS), and ultrahigh molecular weight polyethylene (UHMWPE) were created through a twin screw compounding process to produce novel polymer blends compatible with ME3DP platforms. Mechanical testing and fractography were used to characterize the different physical properties of these new blends. Though the new blends possessed different physical properties, compatibility with ME3DP platforms was maintained. Also, a decrease in surface roughness of a standard test piece was observed for some blends as compared with ABS.
Journal Article
On-admission anemia predicts mortality in COVID-19 patients: A single center, retrospective cohort study
by
Vivek, Kumar
,
Choi, Jaeun
,
Nair, Singh
in
Acute Kidney Injury - epidemiology
,
Aged
,
Aged, 80 and over
2021
We investigated the impact of anemia based on admission hemoglobin (Hb) level as a prognostic risk factor for severe outcomes in hospitalized patients with coronavirus disease 2019 (COVID-19).
A single-center, retrospective cohort study was conducted from a random sample of 733 adult patients (age ≥ 18 years) obtained from a total of 4356 laboratory confirmed SARS-CoV-2 cases who presented to the Emergency Department of Montefiore Medical Center between March–June 2020. The primary outcome was a composite endpoint of in-hospital severe outcomes of COVID-19. A secondary outcome was in-hospital all-cause mortality.
Among the 733 patients included in our final analysis, 438 patients (59.8%) presented with anemia. 105 patients (14.3%) had mild, and 333 patients (45.5%) had moderate-severe anemia. Overall, 437 patients (59.6%) had a composite endpoint of severe outcomes. On-admission anemia was an independent risk factor for all-cause mortality, (Odds Ratio 1.52, 95% CI [1.01–2.30], p = 0.046) but not for composite severe outcomes. However, moderate-severe anemia (Hb < 11 g/dL) on admission was independently associated with both severe outcomes (OR1.53, 95% CI [1.05–2.23], p = 0.028) and mortality (OR 1.67, 95% CI [1.09–2.56], p = 0.019) during hospitalization.
Anemia on admission was independently associated with increased odds of all-cause mortality in patients hospitalized with COVID-19. Furthermore, moderate-severe anemia (Hb <11 g/dL) was an independent risk factor for severe COVID-19 outcomes. Moving forward, COVID-19 patient management and risk stratification may benefit from addressing anemia on admission.
Journal Article
Additive manufacturing of LiNi1/3Mn1/3Co1/3O2 battery electrode material via vat photopolymerization precursor approach
by
Sreenivasan, Sreeprasad T.
,
MacDonald, Eric
,
Panier, Stéphane
in
3-D printers
,
639/166
,
639/301
2022
Additive manufacturing, also called 3D printing, has the potential to enable the development of flexible, wearable and customizable batteries of any shape, maximizing energy storage while also reducing dead-weight and volume. In this work, for the first time, three-dimensional complex electrode structures of high-energy density LiNi
1/3
Mn
1/3
Co
1/3
O
2
(NMC 111) material are developed by means of a vat photopolymerization (VPP) process combined with an innovative precursor approach. This innovative approach involves the solubilization of metal precursor salts into a UV-photopolymerizable resin, so that detrimental light scattering and increased viscosity are minimized, followed by the in-situ synthesis of NMC 111 during thermal post-processing of the printed item. The absence of solid particles within the initial resin allows the production of smaller printed features that are crucial for 3D battery design. The formulation of the UV-photopolymerizable composite resin and 3D printing of complex structures, followed by an optimization of the thermal post-processing yielding NMC 111 is thoroughly described in this study. Based on these results, this work addresses one of the key aspects for 3D printed batteries via a precursor approach: the need for a compromise between electrochemical and mechanical performance in order to obtain fully functional 3D printed electrodes. In addition, it discusses the gaps that limit the multi-material 3D printing of batteries via the VPP process.
Journal Article