Comparative levels and survival of naturally occurring microorganisms deposited on surfaces through handling and aerial fallout a preliminary report

Death rates of microorganisms deposited on surfaces of stainless steel and electronic components by handling and aerial fallout - Decontamination technique

Recovery of Viable Microorganisms from Solids. I - Model Systems

Solidification process for recovering viable microorganisms to aid spacecraft sterilization procedure

Surface topography of hydroxyapatite affects ROS17/2.8 cells response

Hydroxyapatite (HA) has been used in orthopedic, dental, and maxillofacial surgery as a bone substitute. The aim of this investigation was to study the effect of surface topography produced by the presence of microporosity on cell response, evaluating: cell attachment, cell morphology, cell proliferation, total protein content, and alkaline phosphatase (ALP) activity. HA discs with different percentages of microporosity (< 5%, 15%, and 30%) were confected by means of the combination of uniaxial powder pressing and different sintering conditions. ROS17/2.8 cells were cultured on HA discs. For the evaluation of attachment, cells were cultured for two hours. Cell morphology was evaluated after seven days. After seven and fourteen days, cell proliferation, total protein content, and ALP activity were measured. Data were compared by means of ANOVA and Duncan’s multiple range test, when appropriate. Cell attachment (p = 0.11) and total protein content (p = 0.31) were not affected by surface topography. Proliferation after 7 and 14 days (p = 0.0007 and p = 0.003, respectively), and ALP activity (p = 0.0007) were both significantly decreased by the most irregular surface (HA30). These results suggest that initial cell events were not affected by surface topography, while surfaces with more regular topography, as those present in HA with 15% or less of microporosity, favored intermediary and final events such as cell proliferation and ALP activity

Financial distress, corporate takeovers and the distress anomaly

Purpose: This paper examines the relation between takeover likelihood and the documented underperformance of distressed company stocks while exploring two competing hypotheses. The failure risk explanation predicts lower returns to distressed firms with high probability of being acquired because the acquisition reduces risk and investors\u27 required return. Conversely, the agency conflicts explanation predicts lower returns when acquisition is unlikely. Design/methodology/approach: The likelihood of receiving a takeover bid is estimated, and portfolio tests explore the underperformance of distressed company stocks relative to non-distressed stocks across varying levels of takeover likelihood. Predictive regressions subsequently examine the relation between distress, takeover exposure and future firm operating performance including how the relation is affected by state anti-takeover laws. Findings: Distressed stocks underperform non-distressed company stocks by economically and statistically significant margins when takeover likelihood is low, yet there is no evidence of underperformance among distressed stocks with moderate or high takeover exposure. Consistent with agency conflicts playing a key role, distressed firms that are disciplined by takeover threats invest more, use more leverage and experience higher future profitability. State-level anti-takeover legislation limits this disciplinary effect, however. Originality/value: The results show that the well-documented distress anomaly is driven by a subset of distressed firms whose managers face limited pressure from the external takeover market. The evidence casts doubt on the failure risk explanation and suggests that agency conflicts play a key role

Friction stir consolidation of aluminium chips: A new approach to overcome the inhomogeneous properties of the consolidated billet

The need to improve the recycling process of metals to achieve sustainability goals is reflected in the growing interest in solid-state recycling approaches. One of these is the Friction Stir Consolidation (FSC), able to directly transform chips into consolidated billets. The main features of this process are the pressure and the rotational speed of the tool which compresses and heats up the chips collected inside a designed die. During the consolidation process, the friction between the tool and chips surfaces plays an important role because it is the main source of heat, therefore the heat transfer starts near the tool to the bottom of the billet resulting in an inhomogeneous material property. This aspect leads to both inhomogeneous microstructure and hardness characterization of the consolidated billet. To improve the effectiveness of the friction stir consolidation recycling process, this study focused on a numerical approach by proposing a new setup in which the structure where the die and the chips are placed on, namely backing plate, was heated up aiming to activate a heat flow also from the bottom

Applying human factors principles to alert design increases efficiency and reduces prescribing errors in a scenario-based simulation

OBJECTIVE: To apply human factors engineering principles to improve alert interface design. We hypothesized that incorporating human factors principles into alerts would improve usability, reduce workload for prescribers, and reduce prescribing errors. MATERIALS AND METHODS: We performed a scenario-based simulation study using a counterbalanced, crossover design with 20 Veterans Affairs prescribers to compare original versus redesigned alerts. We redesigned drug-allergy, drug-drug interaction, and drug-disease alerts based upon human factors principles. We assessed usability (learnability of redesign, efficiency, satisfaction, and usability errors), perceived workload, and prescribing errors. RESULTS: Although prescribers received no training on the design changes, prescribers were able to resolve redesigned alerts more efficiently (median (IQR): 56 (47) s) compared to the original alerts (85 (71) s; p=0.015). In addition, prescribers rated redesigned alerts significantly higher than original alerts across several dimensions of satisfaction. Redesigned alerts led to a modest but significant reduction in workload (p=0.042) and significantly reduced the number of prescribing errors per prescriber (median (range): 2 (1-5) compared to original alerts: 4 (1-7); p=0.024). DISCUSSION: Aspects of the redesigned alerts that likely contributed to better prescribing include design modifications that reduced usability-related errors, providing clinical data closer to the point of decision, and displaying alert text in a tabular format. Displaying alert text in a tabular format may help prescribers extract information quickly and thereby increase responsiveness to alerts. CONCLUSIONS: This simulation study provides evidence that applying human factors design principles to medication alerts can improve usability and prescribing outcomes

Cryptocurrency return reversals

Analysing a set of 200 cryptocurrencies over the period from 2015 to 2019, we document a significant return reversal effect that holds at the daily, weekly, and monthly rebalancing frequencies and is robust to controls for differences in size, turnover, and illiquidity. Moreover, the reversal effect persists during both halves of our sample period and following periods of both high and low market implied volatility. Consistent with the effect being driven by a combination of market inefficiency and compensation for liquidity provision, we find reversals are most pronounced among smaller capitalization and less liquid cryptocurrencies

Bilayered Calcium Sulfate/Calcium Phosphate Space-Making Composites with Multiple Drug Delivery Capabilities

The present invention provides for bilayered composites that provide for sustained drug delivery and support to recovering tissue(s) and areas surrounding, such as with bone tissue. The two layers degrade at separate rates, thereby providing sustained mechanical support and tailored drug delivery

An insight into friction stir consolidation process mechanics through advanced numerical model development

Friction stir consolidation (FSC) is a solid-state process adopted to recycle machining scraps with aim to reduce the adverse impact of obtaining metals from their primary source. FSC was also applied to offer plausible new routes for alloying and upcycling from powder and scrap metal and thus drew the attention of many researchers. During FSC process, a rotating tool with a certain force is applied to a given chips batch enclosed in a die chamber turning it into a consolidated billet. It is assumed that favorable process conditions for chips bonding are acquired by the combined effect of friction, stirring action, and pressure of the tool. However, the real process is quite complex, and it can be understood only by developing proper solid bonding criteria through numerical modeling that can forecast the consolidation process. Therefore, in this research, an attempt was made to implement different existing bonding criteria. Some of these were good enough to predict favorable conditions for sound bonding of particular case studies, however a uniform criteria with a single threshold value that is applicable to all case studies could not be achieved. Therefore, this study suggests for a new approach to accurately predict the bonding integrity of the FSC process

A generalized parametric model for the bonding occurrence prediction in friction stir consolidation of aluminum alloys chips

Over the last years solid state processing has been applied as an environmentally friendly recycling method for metal scrap. These approaches, by skipping the melting step, allow substantial energy and resource savings with respect to conventional remelting routes. Specifically, several processes relying on solid bonding phenomenon have been applied to recycle aluminum alloys chips. In this paper, the Friction Stir Consolidation recycling process is considered as solid-state recycling approach to turn chips of three different aluminum alloys namely AA2024, AA6082 and AA5083, into consolidated billet. The paper aims both at validating a new solid bonding criteria specifically designed for Friction Stir Consolidation as well as at proposing a general model to characterize the bonding criterion for each single considered material. In this regard, a correlation analysis and a new parametric model has been developed aiming to understand which material properties were involved in solid bonding occurrence and to predict the bonding limit curve vs temperature by means of material thermomechanical properties. The identified criterion and parametric model have been validated by implementing these on the bonding prediction occurrence in Friction Stir Consolidation of AA5083 aluminum chips. Results revealed that just on the basis of some mechanical and thermal properties of the material to be recycled it is possible to identify the threshold for the actual bonding of the material at different temperature levels and, therefore, properly design the recycling process by means of numerical simulation implementation