The following is a guest post by Katherine Blood, Curator of Fine Prints, Prints & Photographs Division. As the Library of Congress marks its 220th year of serving the nation, the publication of a new guide tells two stories: how staff have for decades worked with art professionals to build the collections and how by […]

The only way to solubilize many antigens for immunoprecipitation is by denaturation. This cell lysis protocol is ideally suited for this purpose to release proteins from complex structures or reveal antibody epitopes hidden within native proteins. Short linear epitopes may not be accessible to antibodies within the native tertiary and quaternary protein structures, but they become exposed upon the unraveling of proteins, exposing their secondary structure. Antibodies otherwise not suitable for the immunoprecipitation of proteins prepared under nondenaturing conditions are now able to bind these antigens of interest in cell lysates prepared under denaturing conditions. These antibodies may also work well for immunoblotting purposes when the protein target is completely denatured. Harvested cells in this protocol are washed in tris-buffered saline (TBS) before lysis in 2% sodium dodecyl sulfate (SDS)-containing Lysis buffer for 10 min at 100°C. The resulting sample is diluted 20-fold in TBS to reduce the SDS concentration to ≤0.1% before the addition of an antibody for immunoprecipitation. Addition of 2% bovine serum albumin (BSA) or 0.1% Nonidet P-40 to the TBS before an immunoprecipitation, respectively, ensures either removal of SDS from the target protein or retaining denatured proteins in solution.

Differential detergent fractionation of cells is a rapid method for extraction of cytoplasmic and nuclear proteins in preparation of an immunoprecipitation. This method can be applied for use of adherent or suspension cells and can significantly reduce nonspecific background in an immunoprecipitation by separation of cellular compartments into individual fractions. The lysis of cells by differential detergents permits the rapid extraction of proteins from the cytoplasm (digitonin), the cytoplasmic membranes, and organelles (Triton X-100), and nucleoplasm (Tween/DOC), facilitated through the use of distinct extraction buffers. Cytoplasmic and nuclear matrix proteins as well as DNA are left behind during the detergent-based extraction.

This rapid and efficient method to prepare highly purified recombinant adeno-associated viruses (rAAVs) is based on binding of negatively charged rAAV capsids to an anion-exchange resin that is pH dependent.

This is a simple method for rapid preparation of recombinant adeno-associated virus (rAAV) stocks, which can be used for in vivo gene delivery. The purity of these vectors is considerably lower than that obtained by either CsCl gradient centrifugation or by combination of iodixanol gradient ultracentrifugation followed by column chromatography.

The most commonly used method for production of recombinant adeno-associated virus (rAAVs) in research laboratories is by transient triple transfection of 293 cells with AAV cis and trans plasmids and an adenovirus helper plasmid. This protocol describes the processes required to prepare the transfected cell suspension for virus purification.

Purified RNA may need to be concentrated by precipitation for downstream applications. Precipitation of RNA with ethanol (or isopropanol) is the standard method to recover RNA from aqueous solutions.

In this protocol, DNA fragments are separated according to size by electrophoresis through low-melting-temperature agarose, and then recovered by melting the agarose and extracting with phenol:chloroform. The protocol works best for DNA fragments ranging in size from 0.5 to 5.0 kb. Yields of DNA fragments outside this range are usually lower, but often are sufficient for many purposes.

Mice, rats, or hamsters are immunized by giving biweekly injections of a purified antigen, cultured cells, or cDNA. For mice, if a pure, soluble protein antigen is being used and is abundant, a dose of 50–100 µg in adjuvant at each immunization is a sensible general recommendation; for rats and hamsters, a dose of 100–200 µg is sufficient. Lower doses can be used for antigens with higher immunogenicity. Adjuvants (Freund's, Ribi, Hunter's TiterMax, ImmunEasy, or Alum) should be mixed with the immunizing antigen for the first two immunizations only; Complete Freund's adjuvant is only used with the first immunization. Subsequent immunizations are performed in phosphate-buffered saline (PBS) or normal saline, with or without Incomplete Freund's adjuvant. The choice of adjuvant is dependent on the subclass of immunoglobulin required. Over the course of the 6-wk immunization schedule, each animal usually receives a total of six injections (three subcutaneous and three intraperitoneal). Once a good titer has developed against the antigen of interest, regular boosts and bleeds are performed to collect the maximum amount of serum. For rats and hamsters, boosts should be spaced every 2–3 wk, and serum samples of 400–500 µL should be collected 10–12 d after each boost. For mice, boosts should be spaced every 2–3 wk, and serum samples of 200–300 µL should be collected 10–12 d after each boost.

The Bradford assay is a quick and fairly sensitive method for measuring the concentrations of proteins. It is based on the shift in absorbance maximum of Coomassie Brilliant Blue G-250 dye from 465 to 595 nm following binding to denatured proteins in solution.

Successful modification of the bacterial artificial chromosome (BAC) after two-step BAC engineering is confirmed in two separate polymerase chain reactions (PCRs). The first reaction (5' co-integrate PCR) uses a forward 5' co-integrate primer (a sequence located upstream of the 5' end of the A-box) and a reverse 3' primer on the vector (175PA+50AT) or within the reporter sequence or mutated region as appropriate. The second reaction (3' co-integrate PCR) uses a forward 5' primer on the recA gene (RecA1300S) and a reverse 3' co-integrate primer (a sequence located downstream from the 3' end of the B-box). Those colonies shown to be positive in PCR analysis are further tested for sensitivity to UV light. After the resolution, colonies that have lost the excised recombination vector including sacB and recA genes become UV light sensitive.

Bacterial artificial chromosome (BAC) clones are rendered electrocompetent and transformed with the recombinant shuttle vector, pLD53SCAB/AB-box. Cointegrates are selected by growth on chloramphenicol and ampicillin to ensure recombination of the shuttle vector into the BAC.

Plasmid DNA is prepared from the recombinant shuttle vector pLD53.SCAB/A-B created by cloning of the A and B homology arms for two-step bacterial artificial chromosome (BAC) engineering. To confirm that the A-box and B-box arms have been successfully incorporated into pLD53.SCAB, the pattern of enzyme digestion of the modified plasmid is compared with that of the unmodified pLD53.SCAB. Once the shuttle vector is shown to carry the proper sequences, it is ready for transfer into the BAC host.

The 700-bp A homology arm (A-box) and the 700-bp B homology arm (B-box) are amplified by polymerase chain reaction (PCR) using purified bacterial artificial chromosome (BAC) DNA as template for two-step BAC engineering. The resulting A-box PCR product contains an AscI site at its 5' end (the 5' primer incorporates an AscI site, and the 3' primer does not incorporate any restriction sites). The B-box PCR product contains an XmaI site at its 3' end (the 5' primer does not incorporate any restriction sites, and the 3' primer incorporates an XmaI site). The amplification products are then digested with the appropriate restriction endonucleases to render them suitable for cloning into the shuttle vector.

In two-step bacterial artificial chromosome (BAC) engineering, a single plasmid is introduced into the BAC-carrying cell lines. The shuttle vector pLD53.SCAB (or pLD53.SCAEB) carries the recA gene and the R6K origin, which requires the protein to replicate. PIR2 cells, expressing , are typically used for the amplification of the vector and maintain about 15 copies/cell of the donor vector, which is relatively stable in this host.

CPMI report: Payment aspects of financial inclusion in the fintech era, April 2020

FSI Briefs No 1, April 2020. Regulatory policy responses should seek to support economic activity while preserving the financial system's soundness and ensuring transparency. The recommendation for banks to make full use of capital and liquidity buffers should go hand in hand with restrictions on dividends and bonuses and clarity concerning the process for rebuilding them. Flexibility in loan classification criteria for prudential and accounting purposes should be complemented with sufficient disclosure on the criteria banks use to assess creditworthiness. The publication of detailed guidance on the application of expected loss provisioning rules, combined with sensible transitional arrangements, may constitute a balanced approach to mitigating the unintended effects of the new accounting standards.

FSI Briefs No 2, April 2020. Guidance issued by financial sector authorities in response to the Covid-19 crisis seems to suggest that international efforts to come up with operational resilience standards should take into account at least the following elements: Critical/essential employees: identifying the critical functions and employees that support important business services, as well as ensuring employees' safety and that they can safely resume their duties (remotely, if necessary); IT infrastructure: ensuring that IT infrastructure can support a sharp increase in usage over an extended period and taking steps to safeguard information security; Third-party service providers: ensuring that external service providers and/or critical suppliers are taking adequate measures and are sufficiently prepared for a scenario in which there will be heavy reliance on their services; Cyber resilience: remaining vigilant in order to identify and protect vulnerable systems, and detect, respond and recover from cyber attacks..

Using a cross-country sample of bank-dependent public fi rms we study the international spillovers of a change in banking regulation on corporate borrowing. For identi cation we examine how US rms' liabilities vis-a-vis banks, non-bank lenders and bond markets evolve after an increase in capital requirements implemented by the European Banking Authority (EBA) in 2011. We find that US firms experience a reduction in credit lines but not in term loans from EU banks.

FSI Briefs No 3, April 2020. In response to the 2007-09 Great Financial Crisis (GFC), accounting standard setters introduced a new methodology to value loans based on expected credit losses (ECL). The previous approach, based on incurred losses, was viewed as procyclical and inconsistent with prudential objectives. In the wake of the Covid-19 pandemic, several prudential authorities and the Basel Committee on Banking Supervision (BCBS), introduced a series of measures to clarify how banks should consider various public and private debt relief programmes in their ECL estimates and in their calculation of regulatory capital. These measures are intended to incentivise banks to continue supporting the real economy, while reducing pressure on banks' ECL provisions, earnings and regulatory capital. Supervisory initiatives that provide capital relief should be augmented by severe constraints on the payment of dividends, bonuses and share buybacks. These joint actions will simultaneously expand banks' lending capacity and enhance their ability to absorb losses. Prudential authorities face difficult trade-offs as they confront the most severe economic crisis in modern times. Encouraging the use of flexibility in applicable accounting standards, while preserving market trust and transparency in the reported financial statements of banks, will be key in fostering both economic and financial stability.

BIS Bulletin No 8, April 2020. Information on local labour markets and Google searches can be used to construct a measure of the vulnerability of employment in different regions of the United States to the Covid-19 shock. Regional exposure to Covid-19 varies significantly, ranging from a low of 2% to a high of 98% of total local employment. We test for the usefulness of the Covid-19 exposure measure by showing that areas with higher exposure report more Google search queries related to the pandemic and unemployment benefits.

This paper reviews post-crisis financial regulatory reforms, examines how they fit together and identifies open issues. Specifically, it takes stock of the salient new features of bank and CCP international standards within a unified analytical framework.

Recent literature has highlighted that international trade is mostly priced in a few key vehicle currencies, and is increasingly dominated by intermediate goods and global value chains (GVCs). Taking these features into account, this paper reexamines the business cycle dynamics of international trade and its relationship with monetary policy and exchange rates.

Our ongoing celebration of the Library of Congress National Book Festival continues with Poets Laureate Tracy K. Smith and Robert Hass discussing the making of poetry, the position of Poet Laureate and their new books, "American Journal: Fifty Poems for Our Time" (edited by Smith) and "A Little Book on Form: An Exploration into the Formal Imagination of Poetry" (Hass), on the Poetry & Prose stage at the 2018 Festival.

Our ongoing celebration of the Library of Congress National Book Festival continues with presidential scholar Annette Gordon-Reed discussing "The Hemingses of Monticello: An American Family" on the Special Programs stage at the 2015 Festival.

Our ongoing celebration of the Library of Congress National Book Festival continues with crime writer Patricia Cornwell discussing "Red Mist,” her 19th Kay Scarpetta novel, on the Fiction & Mystery stage at the 2012 Festival.

Our ongoing celebration of the Library of Congress National Book Festival continues with young adult and fantasy author Leigh Bardugo discussing "Crooked Kingdom" on the Genre Fiction stage at the 2018 Festival. This post includes prompts for writing and thinking that young readers, families and teachers can use to explore the author and the author’s work—recommended for ages 13+.

Our ongoing celebration of the Library of Congress National Book Festival continues with former Secretary of State Condoleezza Rice discussing "Democracy: Stories from the Long Road to Freedom" on the Main Stage at the 2017 Festival.

Our ongoing celebration of the Library of Congress National Book Festival continues with two-time Pulitzer Prize-winning novelist Colson Whitehead discussing "Zone One" on the Poetry & Prose stage at the 2012 Festival.

Our ongoing celebration of the Library of Congress National Book Festival continues with historian Michael Beschloss discussing “Presidents of War” on the Main Stage at the 2019 Festival.

Our ongoing celebration of the Library of Congress National Book Festival continues with crime and mystery writer Karin Slaughter discussing "Broken," part of her Will Trent series, on the Fiction & Mystery stage at the 2010 Festival.

Our ongoing celebration of the Library of Congress National Book Festival continues with actor and author Neil Patrick Harris discussing "The Magic Misfits: The Minor Third." The event, part of the new year-long National Book Festival Presents series, took place in the Library’s Coolidge Auditorium. This post includes prompts for writing and thinking that young readers, families and teachers can use to explore the author and the author’s work—recommended for ages 8+.

British product designer Lucy Hughes has invented a biodegradable plastic made from fish offcuts

Architects and planners from the Netherlands are advising coastal cities worldwide on how to live with water

Press release about the Basel Committee publishing consultation paper on revisions to the credit valuation adjustment risk framework, 28 November 2019.

BIS Press Release - Easing trade tensions lift sentiment: BIS Quarterly Review, 8 December 2019

Press release: CPMI and IOSCO share authorities´ experiences in cooperation to increase FMI safety and efficiency, 10 December 2019

Press release: CPMI report sets out considerations for developers of wholesale digital tokens, 12 December 2019

The BIS Board of Directors has decided to invite the central banks of Kuwait, Morocco and Vietnam to become members of the BIS. This is the first such expansion since 2011 and will take the number of members to 63.

Markets Committee calls for wider adoption of global code of conduct for foreign exchange markets (Press release, 30 January 2020)

No global real estate market despite higher price synchronisation and growing role of international investors, central banks find (Press release, 18 February 2020)

The Bank for International Settlements (BIS) today announced two key appointments to the BIS Innovation Hub, a new initiative designed to support central bank collaboration on new financial technology. (Press release, 19 February 2020)

Basel Committee Press release "Basel Committee meets to review vulnerabilities and emerging risks, advance supervisory initiatives and promote Basel III implementationl", 27 February 2020.

Press release about Basel Committee assesses members' implementation of the Net Stable Funding Ratio and large exposures framework, 19 March 2020

Press release "Governors and Heads of Supervision announce deferral of Basel III implementation to increase operational capacity of banks and supervisors to respond to Covid-19", 27 March 2020

BCBS Press release "Basel Committee sets out additional measures to alleviate the impact of Covid-19", 3 April 2020

BCBS Press release "Basel Committee and IOSCO announce deferral of final implementation phases of the margin requirements for non-centrally cleared derivatives", 3 April 2020