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Titanium is the metal of choice for many implantable devices including dental prostheses, orthopaedic devices and cardiac pacemakers. Titanium and its alloys are favoured for hard tissue replacement because of their high strength to density ratio providing excellent mechanical properties and biocompatible surface characteristics promoting in-vivo passivation due to spontaneous formation of a native protective oxide layer in the presence of an oxidizer. This study focuses on the development of a three-dimensional chemical, mechanical, surface nano-structuring (CMNS) process to induce smoothness or controlled nano-roughness on the bio-implant surfaces, particularly for applications in dental implants. CMNS is an extension of the chemical mechanical polishing (CMP) process. CMP is utilized in microelectronics manufacturing for planarizing the wafer surfaces to enable photolithography and multilayer metallization. In biomaterials applications, the same approach can be utilized to induce controlled surface nanostructure on three-dimensional implantable objects to promote or demote cell attachment. As a synergistic method of nano-structuring on the implant surfaces, CMNS also makes the titanium surface more adaptable for the bio-compatible coatings as well as the cell and tissue growth as demonstrated by the electrochemical and surface wettability evaluations on implants prepared by DI-water machining versus oil based machining.

Copper is a commonly used interconnect metal in microelectronic interconnects due to its exceptional electrical and thermal properties. Particularly in applications of the 2.5 and 3D integration, Cu is utilized in through-silicon-vias (TSVs) and flip chip interconnects between microelectronic chips for providing miniaturization, lower power and higher performance than current 2D packaging approaches. SnAg capped Cu pillars are a common high-density interconnect technology for flip chip bonding. For these interconnects, specific properties of the Cu surface, such as roughness and cleanliness, are an important factor in the process to ensure quality solder bumps. During electroplating, tight processing parameters must be met so that defects are avoided, and high bump uniformity is achieved. An understanding of the interactions at the solder and Cu pillar interface is needed, based on the electroplating parameters, to determine the best method for populating solder on the wafer surface. In this study, surface treatment techniques such as oxygen plasma cleaning were performed on the Cu surfaces and the SnAg plating chemistry for depositing the solder were evaluated through hull cell testing to qualitatively determine the range of current densities to investigate. It was observed that current density while plating played a large role in solder bump deposition morphology. At the higher current densities greater than 60 mA/cm2, bump height non-uniformity and dendritic growth are observed and at lower current densities, less than or equal to 60 mA/cm2, uniform, continuous bump height occurred.

We report on the effect of β-Ga2O3 crystal orientation on wet etching and Ohmic contact formation. The photochemical etching rate in KOH solutions of ( 2 ¯ 01 ) oriented, n-type bulk single crystals grown by the edge-defined film-fed growth method is ∼3–4 times higher than for the (010) planes. The activation energy for etching was 0.498 eV and 0.424 eV for ( 2 ¯ 01 ) and (010) orientations, respectively, suggesting the etching is reaction-limited with the same rate-limiting step. Ti (200 A)/Au (1500 A) metallization deposited on the two different orientations and annealed at 450 °C showed Ohmic current-voltage (I-V) behavior for ( 2 ¯ 01 ) but rectifying characteristics for (010). For (010) Ga2O3, there exists 2 types of surfaces having Ga and O atomic densities of 0.58 and 0.87 × 1015 cm−2, respectively. By contrast, for ( 2 ¯ 01 ) Ga2O3 surfaces, there exist 2 types of surface, with each type terminated with only Ga or O. If the surface is terminated with O, the dangling bond densities of O are 1.78 and 2.68 × 1015 cm−2, respectively. We found that ( 2 ¯ 01 ) –oriented Ga2O3 is etched at higher rates and is easier to form Ohmic contacts than (010) Ga2O3. The higher density of oxygen dangling bonds on the ( 2 ¯ 01 ) plane correlates with the faster etch rates and pronounced Ohmic behavior from deposited metals.

Nano-scale modification of macro-scale 3-dimensional implantable devices is gaining more attention as the cell attachment/detachment mechanisms at the bio-interfaces are profoundly affected by the nanoscale interfacial interactions [1]. Titanium based biomaterials are widely used for dental prostheses, orthopedic devices and cardiac pacemakers. Titanium and its alloys are most favored for hard tissue replacement due to their excellent mechanical properties and surface characteristics promoting biocompatibility due to spontaneous formation of a thick oxide layer in the presence of an oxidizer. This study focuses on the development of a three dimensional chemical mechanical nano-structuring (CMNS) process to induce smoothness or controlled nano-roughness on the bio-implant surfaces, particularly for an application on the dental implants. CMNS is an extension of the chemical mechanical polishing process. CMP is utilized in microelectronics manufacturing for planarizing the wafer surfaces to enable photolithography and multilayer metallization. In biomaterials applications, it has been shown that the same approach can be utilized to induce controlled surface nano-structure on 3-D implants to promote or demote cell attachment [2]. By tuning the polishing slurry particle size, solids loading and the chemical composition, both the chemical nature and the surface topography can be modified to make the surface very smooth or rough at nano-scale. This new technique helps produce implant surfaces that are cleaned from potentially contaminated surface layers by removing a nano-scale top layer while simultaneously creating a protective oxide film on the surface to limit any further contamination to minimize risk of infection [3]. As a synergistic method of nano-structuring on the implant surfaces, CMNS also modifies the mechanical properties on the implant surfaces and makes the titanium surface more adaptable for the bio-compatible coatings as well as the cells and tissue growth as demonstrated by the mechanical, electrochemical and biological evaluations. The ability of manipulating the surface nanostructure is also essential to understand the fibroblast and osteoblast cell attachment/detachment mechanisms on the implant surfaces to enable functionality of the implants whether the biocompatibility is a function of the cell attachment such as in the dental or prosthetic implants or limited attachment is needed for the functionality such as for the cardiac valves. Staruch, R, Griffin, M, Butler, P. Nanoscale surface modifications of orthopaedic implants: state of the art and perspectives. Open Orthop J 2016; 10: 920–938. Ozdemir, Z., Ozdemir, A., Basim, G.B. “Biomedical Applications of Chemical Mechanical Polishing”, Materials Science and Engineering - Part C., 68 (1), P 383-396, 2016. Ozdemir, Basim, G.B. "Effect of Chemical Mechanical Polishing on Surface Nature of Titanium Implants FT-IR and Wettability Data of Titanium Implants Surface After Chemical Mechanical Polishing Implementation," Data, in Brief, 10, P 20-25, 2017.

BACKGROUND AND OBJECTIVES: Unplanned extubation can be a significant event that places the patient at risk for adverse events. Our goal was to reduce unplanned extubations to METHODS: All unplanned extubations in the NICU beginning in October 2009 were audited. Data collected included time of day, patient weight, and patient care activity at the time of the event. Bundles of potentially better practices were implemented in sequential Plan-Do-Study-Act cycles. Rates of unplanned extubation (number per patient-intubated day) for each month were analyzed by using control charts, and causes of unplanned extubation were analyzed by using Pareto charts. RESULTS: We found a significant decrease in the unplanned extubation rate after implementation of the first bundle of potentially better practices in May 2010 (2.38 to 0.41 per 100 patient-intubated days). Several more Plan-Do-Study-Act cycles were conducted to sustain this improvement. A persistent reduction in the unplanned extubation rate (0.58 per 100 patient-intubated days) began in February 2013. Causes included dislodgement during care and procedures and variation in the fixation of the endotracheal tube. The majority of events occurred in very low birth weight infants during the daytime shift. CONCLUSIONS: Unplanned extubations in the NICU can be reduced by education of staff and by implementing standard practices of care. Sustainability of any practice change to improve quality is critically dependent on culture change within the NICU. We suggest that the benchmark for unplanned extubation should be a rate

An exploratory investigation was conducted to examine the implementation of the first self-run, communal-living setting based on the Oxford House model, in the United Kingdom (UK). A cross-sectional, mixed methods design was used to examine the Oxford House model’s total abstinence approach to recovery from substance use disorders among residents (n = 7) living in the first Oxford House established in the UK. Several measures commonly used in addiction research and personal narratives were used to assess residents’ response to Oxford House living. Findings suggest that the Oxford House model is a post-treatment intervention that meets the needs of individuals seeking an abstinence-based recovery from alcohol and/or drug dependence in the UK.

Sociocultural and economic limitations often deprive individuals of the freedoms to make decisions regarding their lives, hindering development. This article presents the Framework for Enabling Empowerment (FrEE), a model that emphasizes the importance of psychosocial factors and the individual in accessing freedoms and promoting health, productivity, and sustainable human development. FrEE is theoretically based in Amartya Sen's Capability Approach. Explaining the synergy between the context, the person, and psychosocial factors, FrEE provides a strategy to achieve the expansion of individual choice and freedoms. The authors present FrEE and its relationship to Sen's theories and explain how FrEE makes the Capability Approach operative. Finally the authors draw on empirical program evaluations in Mexico to discuss FrEE's potential impact on the field of human development.

Zika virus detection was demonstrated using antibody-functionalized cover glasses externally connected to the gate electrode of an AlGaN/GaN high electron mobility transistor (HEMT). A pulsed bias voltage of 0.5 V was applied to an electrode on the region of the cover glass region functionalized with antibody, and the resulting changes of drain current of the HEMT were employed to determine the presence of Zika virus antigen concentration ranging from 0.1 to 100 ng/ml. The dynamic and static drain current changes as a function of Zika virus concentration were modeled with a spring-like elastic relaxation model and the Langmuir extension model, respectively. Excellent fits to the data were found with relaxation time constants of antibody and antigen molecules in the range of 11 μs and 0.66–24.4 μs, respectively, for the concentration range investigated. The ratio of antibody bound with antigen to the total available antibody on the functionalized contact window was in the range of 0.013–0.84 for the Zika antigen concentration range of 0.1–100 ng/ml. Since the HEMT is not exposed to the bio-solution, it can be used repeatedly. The functionalized glass is the only disposable part in the detection system, showing the potential of this approach for hand-held, low cost sensor packages for point-of-care applications.

Acute treatment aftercare in the form of sober living environments—i.e., recovery houses—provide an inexpensive and effective medium-term treatment alternative for many with substance use disorders. Limited evidence suggests that house-situated social relationships and associated social support are critical determinants of how successful these residential experiences are for their members, but little is known about the mechanisms underlying these relationships. This study explored the feasibility of using dynamic social network modeling to understand house-situated longitudinal associations among individual Alcoholics Anonymous (AA) related recovery behaviors, length of residence, dyadic interpersonal trust, and dyadic confidant relationship formation processes. Trust and confidant relationships were measured 3 months apart in U.S. urban-area recovery houses, all of which were part of a network of substance use recovery homes. A stochastic actor-based model was successfully estimated from this data set. Results suggest that confidant relationships are predicted by trust, while trust is affected by recovery behaviors and length of residence. Conceptualizing recovery houses as a set of independent, evolving social networks that can be modeled jointly appears to be a promising direction for research.

Aldol reactions of chiral aminoaldehydes and methylacrylate in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) produces β-hydroxy methylbutenoates which can be utilized as psuedodipeptides. However, reaction of aminoaldehydes with acrylamide in the presence of DABCO afforded the adducts derived from the addition of the acrylamide nitrogen to the aldehyde to generate N-acylhemiaminals. These reactions were found to proceed at a faster rate than the typical Baylis-Hillman reaction and also require the presence of DABCO.

Aldol reactions of chiral aminoaldehydes and methylacrylate in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) produces β-hydroxy methylbutenoates which can be utilized as psuedodipeptides. However, reaction of aminoaldehydes with acrylamide in the presence of DABCO afforded the adducts derived from the addition of the acrylamide nitrogen to the aldehyde to generate N-acylhemiaminals. These reactions were found to proceed at a faster rate than the typical Baylis-Hillman reaction and also require the presence of DABCO.