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Detection of ultrashort-chain and other per- and polyfluoroalkyl substances (PFAS) in U.S. bottled water
(Elsevier BV)
Per- and polyfluoroalkyl substances (PFAS) are compounds of emerging concern due to their persistence in the global water cycle and detection in drinking water sources. However, PFAS have been poorly studied in bottled water, especially in the United States. This study investigated the occurrence of PFAS and related factors in 101 uniquely labelled bottled water products for sale in the U.S. Products were screened for 32 target PFAS by solid phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS). Fifteen of 32 measured analytes were detected, consisting primarily of C3-C10 perfluorocarboxylic acids (PFCA) and C3-C6 and C8 perfluorosulfonic acids (PFSA). PFAS were detected above method detection limits in 39/101 tested products. The Σ32PFAS concentrations detected were 0.17–18.87 ng/L with a median of 0.98 ng/L; 97% of samples were below 5 ng/L. PFCA (83%) and short-chain perfluoroalkyl acids (PFAA) containing 5 or less CF2 groups (67%) were more prevalent on a mass basis than PFSA and longer-chain PFAA, respectively. Ultrashort-chain PFPrA, measured for the first time in bottled water, accounted for the greatest individual fraction of detected PFAS mass (42%) and was found almost exclusively in products labeled as Spring water. Purified water products contained significantly less PFAS than Spring water products, which was attributed to the use of reverse osmosis (RO) treatment in the majority of Purified waters (25/35) compared to Spring waters (1/45). RO-treated products contained significantly lower Σ32PFAS, long-chain, short-chain, and PFPrA concentrations than products without RO. Although no enforceable PFAS regulations exist for bottled water in the U.S., the finding that some products approach levels of concern justify a framework for monitoring PFAS in bottled water production.
(2023-11) Sweet, Aaliyah
International collaborative research incorporates cross-country groups that allocate research affairs, manage research, and encourage research outcomes to develop comprehension and encourage affirmative alterations in execution. International research can benefit a specific field, incorporating more important influence and extensive pertinence. It also allows us to enlarge research discoveries to various cultures, districts, and communities. Also, international collaborative research offers opportunities to create reciprocally advantageous connections and decipher worldwide issues. However, with international collaboration, the challenges that come with it can also increase. Utilizing responses from questionnaires and articles on international research collaborations, this project aims to display the need for educational programs that can assist research administrators with overcoming barriers to international research collaborations. The responses from the questionnaires demonstrate that research administrators want educational opportunities to gain experience in how to deal with challenges that come from international research collaborations.
Crystalglobulin-associated nephropathy presenting as MGRS in a case of monoclonal B-cell lymphocytosis: a case report
(Springer Science and Business Media LLC)
Abstract Background Crystalglobulin-associated nephropathy (CAN), a rare subtype of monoclonal gammopathy, usually associated with multiple myeloma and occasionally monoclonal gammopathy of uncertain significance (MGUS), is characterized by occluding monoclonal pseudothrombi within renal glomerular capillaries and/or interstitial arterioles. Ultrastructurally, these pseudothrombi are unique for having a crystalline substructure. We describe a case of an adult patient with monoclonal B-cell lymphocytosis (MBL) and acute renal failure whose kidney biopsy revealed a rare diagnosis of CAN. Case presentation A 63-year old male presented with a 2-month history of edema, arthralgia and malaise. He had acute kidney injury with hematoproteinuria on urine analysis. Serum and urine protein electrophoresis were both negative. A renal biopsy however revealed features of CAN. Organomegaly, bone pain and lymphadenopathy were absent. A repeat serum electrophoresis was positive for IgA kappa and a free light chain assay showed elevated free kappa light chains. Flow cytometry done subsequently revealed a diagnosis of MBL, chronic lymphocytic leukemia (CLL) type. Conclusion CAN in association with MBL/CLL has not been previously described in literature, and our case highlights yet another instance of monoclonal gammopathy of renal significance (MGRS) where a small B-cell clone resulted in extensive renal pathology without systemic manifestations.
Evaluating Improvements and Challenges in Affinity Chromatography for AAV Purification
(Johns Hopkins University, 2023-07-31) Dachenko, Alexandra; Betenbaugh, Michael; Hadidi, Mahsa
Purification process development is crucial to the Research and Development (R&D) sector in the biotechnology industry by designing and optimizing downstream unit operations capable of manufacturing safe treatments for clinical trials. Purification is crucial in manufacturing therapeutics such as monoclonal antibodies (mAbs), mRNA, viral vectors, and non-viral vectors. Recently, viral vector gene therapy modalities using adeno-associated viruses (AAVs) have been shown to be an effective therapeutic agent for both rare and common diseases in humans. One of the key polishing steps in the downstream manufacturing process of AAVs is affinity chromatography, where a ligand with specific binding affinity to an AAV serotype is coupled to a base matrix that separates AAVs from host cell contaminants produced in the cell culture process. Column resin is the most common affinity chromatography matrix, but it possesses mass transfer limitations. This report evaluated a prototype affinity membrane device coupled with AVB ligand designed to overcome these mass transfer limitations and decrease process times, while yielding comparable AAV recovery and purity to column resin. The evaluations included dynamic binding capacity (DBC) studies, ligand lifetime studies, and buffer optimizations. The performance of the device was compared to control experiments using two common column resins with the same ligand as the device. The novel membrane device can bind at least 2e14 vg/mL_membrane and can undergo at least 3 cycles without a major binding capacity drop. The recovery of AAV is comparable to column resins; additional process development studies were required to increase recovery values because process parameters used for resin with the same ligand were not effective. A comparison of AAV product purity cannot be made because impurity profiles were not tested. Some recommendations for future work with the availability of more devices include more DBC studies, buffer optimization studies, and testing of the device performance with different AAV serotypes and load material. The prototype membrane device offers unique benefits over column resin for affinity chromatography in its fast flow rates, reusability, and potentially lower costs due to its “prepacked” design; however, the evaluations demonstrated the device does not provide significant enough process improvements that would favor its implementation in place of column resin for the tested material.
Assessing the Effectiveness of U.S. Financial Regulations: A Comparative Analysis with E.U. Responses
(Johns Hopkins University, 2023-09-12) Fassas, Vassilios A.; Wolfson, Dorothea; Rosenthal, Alexander; Harris, Doug
This paper assesses the effectiveness of US financial regulation in carrying out its intended purpose, namely, to adequately protect investors from industry abuse, insider advantages, and fraud. Reviewing recent financial crises, the role of the SEC, high profile Supreme Court cases, and legislation, such findings call into question the legitimacy of the financial system as a whole and is worrying due to Americans’ sheer reliance on banks and securities markets. Furthermore, this paper then compares the U.S. regulatory response with that of the E.U. as a result of the Global Financial Crisis and found that E.U. regulations are more clear, more potent, and more effective in handling and preventing financial crises. This paper uses statistical data, legislative analysis, and testimonial evidence to conclude that there are severe ways in which the US regulatory regime is lacking. Particularly, through vague laws that do not take proper measures to adequately protect against a future crisis, along with the evaluation of the capacity of the SEC to enforce the financial laws in question, US financial regulation does not effectively carry out its intended purpose.
(Johns Hopkins University, 2023-08-31) Broadus, Twais; Wolfson, Dorothea; Rosenthal, Alexande
This study delves into the intricate nexus between personality traits in politics and their influence on electoral outcomes, specifically within the context of U.S. presidential elections from 2000 to 2020. The research utilizes a three-pronged approach: a content analysis of presidential debates to discern strategic trait-mentions, an examination of American National Election Study (ANES) data to capture voter evaluations of candidates based on specific traits, and an exploration of candidates' foreign policy emphasis, reflecting their projection of leadership. Key findings suggest Republicans consistently emphasize traits more than Democrats in debates, and there is noticeable variability in trait preference across partisan lines, particularly among Independents. A shift from domestic to foreign policy considerations was also observed over the years, indicating an electorate more cognizant of international influences on domestic policy. This change allows candidates to demonstrate their leadership skills through their stance on international matters. The culmination of these insights presents a comprehensive view, underscoring the dynamic interplay of candidate personality portrayals, voter preferences, and policy considerations in shaping electoral dynamics. The research emphasizes the imperative for political transparency and robust representation, aiming to demystify leadership roles and promote informed electoral choices for the greater societal benefit.