Sapphire advanced mitigation process: wet etch to expose sub-surface damage and increase laser damage resistance and mechanical strength

A novel, to the best of our knowledge, method of wet chemical etching of sapphire workpieces (such as optics, wafers, windows, and cones), called the sapphire advanced mitigation process (or sapphire AMP), has been developed that exposes sub-surface mechanical damage created during the optical fabrication process and significantly enhances the surface laser damage resistance ($ \gt {2{\times}}$>2×) and mechanical strength (up to $\sim{2.6{\times}}$∼2.6×). Sapphire AMP involves first treating the workpiece with a mixture of sulfuric and phosphoric acid $([{\rm H_{2}{\rm SO_{4}}}]:[{\rm H_{3}{\rm PO_{4}}}]=1:3)$([H₂SO₄]:[H₃PO₄]=1:3) at 220°C, followed with phosphoric acid at 160°C, then with sodium hydroxide base (NaOH) and surfactant at 40°C, and finally with a high-pressure deionized water spray rinse. Sapphire AMP has been demonstrated on both A- and C-plane sapphire workpieces. The mechanism of this etch process involves the reaction of the sapphire $({\rm Al_{2}}{\rm O_{3}})$(Al₂O₃) surface with sulfuric acid $({\rm H_{2}}{\rm SO_{4}})$(H₂SO₄) forming aluminum sulfate $[{{\rm Al}_2}{({{\rm SO}_4})_3}]$[Al₂(SO₄)₃], which has low solubility. The high phosphoric acid content in the first and second steps of sapphire AMP results in the efficient conversion of ${{\rm Al}_2}{({{\rm SO}_4})_3}$Al₂(SO₄)₃ to aluminum phosphate $({\rm AlPO_{4}})$(AlPO₄), which is very soluble, greatly reducing reaction product redeposition on the workpiece surface. Sapphire AMP is shown to expose sub-surface mechanical damage on the sapphire surface created during the grinding and polishing processes, whose etched morphology has either isotropic or anisotropic evolution depending on the nature of the initial surface damage. Sapphire AMP was also designed to remove the key known surface, laser absorbing precursors (namely, foreign chemical impurities, the fracture surface layer of preexisting sub-surface damage, and reaction product or foreign species redeposition or precipitation). Static and sliding indention induced surface microfractures on sapphire are shown after sapphire AMP to have a significant decrease in the fast photoluminescence intensity (a known metric for measuring the degree of laser damaging absorbing precursors). In addition, the onset of laser damage (at 351 nm 3 ns) on sapphire AMP treated workpieces was shown to increase in fluence from $\sim{4}$∼4 to $ \gt {9}.{5}\;{{\rm J/cm}^2}$>9.5J/cm². Finally, biaxial ball-on-ring mechanical tests on sapphire disks showed an increase in the failure stress from 340 MPa (with pre-existing 28 µm flaws) to $\sim{900}\;{\rm MPa}$∼900MPa after sapphire AMP, which is attributed to the blunting of the surface microfractures.

Manufacturing biological medicines on demand: Safety and efficacy of granulocyte colony-stimulating factor in a mouse model of total body irradiation

Protein therapeutics, also known as biologics, are currently manufactured at centralized facilities according to rigorous protocols. The manufacturing process takes months and the delivery of the biological products needs a cold chain. This makes it less responsive to rapid changes in demand. Here, we report on technology application for on-demand biologics manufacturing (Bio-MOD) that can produce safe and effective biologics from cell-free systems at the point of care without the current challenges of long-term storage and cold-chain delivery. The objective of the current study is to establish proof-of-concept safety and efficacy of Bio-MOD-manufactured granulocyte colony-stimulating factor (G-CSF) in a mouse model of total body irradiation at a dose estimated to induce 30% lethality within the first 30 days postexposure. To illustrate on-demand Bio-MOD production feasibility, histidine-tagged G-CSF was manufactured daily under good manufacturing practice-like conditions prior to administration over a 16-day period. Bio-MOD-manufactured G-CSF improved 30-day survival when compared with saline alone (p = .073). In addition to accelerating recovery from neutropenia, the platelet and hemoglobin nadirs were significantly higher in G-CSF-treated animals compared with saline-treated animals (p < .05). The results of this study demonstrate the feasibility of consistently manufacturing safe and effective on-demand biologics suitable for real-time release.

Liquid Chromatographic Method for the Determination of Nine Phenolic Antioxidants in Butter Oil: Collaborative Study

Ten laboratories collaboratively studied a liquid chromatographic (LC) method for the determination of propyl, octyl, and dodecyl gallate (PG, OG, and DG, respectively), 2,4,5-trihydroxybutyrophenone (THBP), ferf-butylhydroquinone (TBHQ), nordihydroguaiaretic acid (NDGA), 2- and 3-tert-butyl-4- hydroxyanisole (BHA), 2,6-di-ferf-butyl-4-hydroxymethylphenol (lonox-100), and 3,5-di-terf-butyl-4- hydroxytoluene (BHT) in butter oil. The 10 samples analyzed were spiked in matched pairs at about 100,50, and 10 μg/g. In the method studied, antioxidants are extracted as in AOAC LC method 983.15, but different LC eluants are used to separate the 9 antioxidants. Results from 1 laboratory were rejected as not valid and were not included in any calculations. For the remaining 9 laboratories, the overall mean recoveries for PG, THBP, TBHQ, NDGA, BHA, OG, lonox, BHT, and DG were 100.9, 97.8,103.4,95.4, 97.4,93.6,95.5,79.0, and 96.2%, respectively. The overall reproducibility relative standard deviations were 8.55,17.4,25.6,14.5,6.60, 9.64,10.8,11.4, and 7.35%, respectively. The method was adopted first action by AOAC International as a modification of AOAC method 983.15.

Determination of Low-Level Glucose and Fructose in Raw and Refined Crystalline Sugar by High-Performance Anion-Exchange Chromatography: Collaborative Study

A method was developed and a collaborative study was performed under the auspices of the International Commission of Uniform Methods for Sugar Analysis. The collaborators used high-performance anion-exchange chromatography (HPAEC) to determine trace amounts of glucose and fructose in 3 raw and 3 refined sugar samples provided as blind duplicates. Fourteen laboratories participated in the study. Although difficulties were experienced by a few analysts, 10 laboratories reported positive results. Average repeatabilities and reproducibilities for glucose and fructose in raw sugar were slightly above 5 and 10%, respectively, and the average Horwitz ratios were well under 2. Average repeatabilities and reproducibilities for glucose and fructose in refined sugar were 10 and 22%, respectively; although the Horwitz ratios were &gt;2, they were marginal (2.8). The HPAEC results agreed with results obtained by gas chromatography in an independent laboratory. Because the method was collaboratively studied according to the protocol of the International Union of Pure and Applied Chemistry for collaborative studies, and the results meet its criteria, it is recommended that the method be adopted Official First Action by AOAC INTERNATIONAL.

Corrigendum to "YaliBricks, a versatile genetic toolkit for streamlined and rapid pathway engineering in Yarrowia lipolytica"

[This corrects the article DOI: 10.1016/j.meteno.2017.09.001.].

Connected diagnostics: linking digital rapid diagnostic tests and mobile health wallets to diagnose and treat brucellosis in Samburu, Kenya

BACKGROUND

Despite WHO guidelines for testing all suspected cases of malaria before initiating treatment, presumptive malaria treatment remains common practice among some clinicians and in certain low-resource settings the capacity for microscopic testing is limited. This can lead to misdiagnosis, resulting in increased morbidity due to lack of treatment for undetected conditions, increased healthcare costs, and potential for drug resistance. This is particularly an issue as multiple conditions share the similar etiologies to malaria, including brucellosis, a rare, under-detected zoonosis. Linking rapid diagnostic tests (RDTs) and digital test readers for the detection of febrile illnesses can mitigate this risk and improve case management of febrile illness.

METHODS

This technical advance study examines Connected Diagnostics, an approach that combines the use of point-of-care RDTs for malaria and brucellosis, digitally interpreted by a rapid diagnostic test reader (Deki Reader) and connected to mobile payment mechanisms to facilitate the diagnosis and treatment of febrile illness in nomadic populations in Samburu County, Kenya. Consenting febrile patients were tested with RDTs and patient diagnosis and risk information were uploaded to a cloud database via the Deki Reader. Patients with positive diagnoses were provided digital vouchers for transportation to the clinic and treatment via their health wallet on their mobile phones.

RESULTS

In total, 288 patients were tested during outreach visits, with 9% testing positive for brucellosis and 0.6% testing positive for malaria. All patients, regardless of diagnosis were provided with a mobile health wallet on their cellular phones to facilitate their transport to the clinic, and for patients testing positive for brucellosis or malaria, the wallet funded their treatment. The use of the Deki Reader in addition to quality diagnostics at point of care also facilitated geographic mapping of patient diagnoses in relation to key risk areas for brucellosis transmission.

CONCLUSIONS

This study demonstrates that the Connected Dx approach can be effective even when addressing a remote, nomadic population and a rare disease, indicating that this approach to diagnosing, treatment, and payment for healthcare costs is feasible and can be scaled to address more prevalent diseases and conditions in more populous contexts.

Faecal Calprotectin and Magnetic Resonance Enterography in Ileal Crohn's Disease: Correlations Between Disease Activity and Long-Term Follow-Up

BACKGROUND AND AIMS

Magnetic resonance enterography [MRE] is the gold standard for assessing ileal inflammation in Crohn's disease [CD]. The aim of the present study was to correlate faecal calprotectin [FC] to MRE via a simple score in an exclusive ileal cohort with long-term follow-up for association with time to surgery or biologic therapy.

METHODS

In total, 150 MRE studies with matched FC [±30 days] were identified from the Edinburgh FC Register [2008-12; n = 18138]. Scans were re-read blinded to clinical data, independently, by two expert gastrointestinal radiologists, to generate a simple MRE score [range 0-10] from assessment of the worst intestinal segment plus total disease extent.

RESULTS

In total, 119 MRE scans were evaluated from 104 patients with ileal CD [L1 or L3 with panproctocolectomy]. Receiver operating characteristic analysis showed an area under the curve of 0.77 [0.67-0.87, p < 0.0001] for FC and MRE score >1, with an optimal cut-off of 145 μg/g for severe inflammation on MRE with 69.3% [57.6-79.5] sensitivity and 71.4% [53.7-85.4] specificity. Long-term follow-up over a median [interquartile range] of 2086 days [1786-2353] revealed FC ≥ 145 μg/g was associated with reduced biologic-free survival until 3 years following MRE, whereas MRE score [severe vs absent] was associated with reduced surgery- and biologic-free survival throughout follow-up. Backwards stepwise logistic regression revealed that length of ileal disease (odds ratio [OR] 3.8, 1.1-13.2, p = 0.034) and increased bowel wall thickness at MRE [OR 4.2, 1.6-10.7, p < 0.0001] or female sex [OR 5.2, 1.5-18.7, p = 0.011] increased the risk of biologic use or surgery, respectively.

CONCLUSIONS

FC correlates well with MRE assessment of ileal CD with MRE parameters associated with long-term biologic- and surgery-free remission.

Genetic Tools for Streamlined and Accelerated Pathway Engineering in Yarrowia lipolytica

Yarrowia lipolytica is an industrial oleaginous yeast that has many attractive physiological and metabolic characteristics for various biotechnological applications. Although it has a long history of industrial applications, the number of genetic tools available to effectively and efficiently engineer Y. lipolytica still falls behind the vast number of tools available for common organisms such as Escherichia coli and Saccharomyces cerevisiae. In this protocol, we have developed a complete and versatile genetic toolkit tailored for facile genetic manipulation in Y. lipolytica. We created a versatile DNA assembly platform YaliBrick, which can streamline the cloning of large multigene pathways with reused genetic parts. We established a sensitive luciferase reporter assay to characterize a set of 12 native promoters. In addition, we used YaliBrick to generate different gene configurations in multigene constructs. The five-gene biosynthetic pathway of the anticancer, antimicrobial pigment violacein was rapidly assembled in 1 week to demonstrate the simplicity and effectiveness of integrating pathway-balancing strategies with our YaliBrick vectors. In the end, we incorporated CRISPR-Cas9 into our YaliBrick vectors and achieved indel mutation and frameshift gene deletion at the CAN1 (arginine permease) genomic loci of Yarrowia lipolytica. The reported protocol provides a standard procedure to streamline and accelerate metabolic pathway engineering in Yarrowia lipolytica.