2,610 research outputs found
Does Function Follow Organizational Form? Evidence From the Lending Practices of Large and Small Banks
Theories based on incomplete contracting suggest that small organizations may do better than large organizations in activities that require the processing of soft information. We explore this idea in the context of bank lending to small firms, an activity that is typically thought of as relying heavily on soft information. We find that large banks are less willing than small banks to lend to informationally 'difficult' credits, such as firms that do not keep formal financial records. Moreover, controlling for the endogeneity of bank-firm matching, large banks lend at a greater distance, interact more impersonally with their borrowers, have shorter and less exclusive relationships, and do not alleviate credit constraints as effectively. All of this is consistent with small banks being better able to collect and act on soft information than large banks.
Does Function Follow Organzizational Form? Evidence From the Lending Practices of Large and Small Banks
Theories based on incomplete contracting suggest that small organizations may do better than large organizations in activities that require the processing of soft information. We explore this idea in the context of bank lending to small firms, an activity that is typically thought of as relying heavily on soft information. We find that large banks are less willing than small banks to lend to informationally “difficult†credits, such as firms that do not keep formal financial records. Moreover, controlling for the endogeneity of bank-firm matching, large banks lend at a greater distance, interact more impersonally with their borrowers, have shorter and less exclusive relationships, and do not alleviate credit constraints as effectively. All of this is consistent with small banks being better able to collect and act on soft information than large banks. The opinions in this paper do not necessarily reflect those of the Federal Reserve Board or its staff. This work has been supported by the National Science Foundation (Rajan, Stein), and the George J. Stigler Center for Study of the State and Economy (Rajan). Thanks also to seminar participants at Yale, the Federal Reserve Bank of New York, Tulane, Babson, the University of Illinois, the Federal Reserve Bank of Chicago Bank Structure Conference, the NBER and the Western Finance Association meetings, as well as to Abhijit Banerjee, Michael Kremer, David Scharfstein, Andrei Shleifer, Greg Udell, Christopher Udry and James Weston for helpful comments and suggestions.
Conservative Management of Median Nerve Brachial Plexopathy after Microwave-based MiraDry Treatment for Axillary Hyperhidrosis
Axillary hyperhidrosis is characterized by excessive sweating of the armpits, which can significantly affect quality of life. A new microwave-based therapy, MiraDry (Miramar labs, Sunnyvale, Calif.), is a promising minimally-invasive treatment option. We report a case of unilateral brachial plexus thermal injury in a thin 19-year-old man treated for axillary hyperhidrosis with the MiraDry system. He initially experienced swelling and pain in the left hand and was prescribed 1 week of methylprednisolone. He then presented 1 week later with induration and swelling of bilateral axillae with swelling of left thumb, left index, and left long fingers, decreased sensation in median nerve distribution of the left hand, and the inability to flex the left index finger DIP joint. EMG showed absent median nerve motor and sensory function, consistent with median nerve plexopathy. He was conservatively managed with close observation and regular occupational hand therapy appointments. At his 12-month follow-up, there was complete return of left pronator teres strength, thumb flexion, and index finger flexion. Decreased sensation remained at the tip of the left index finger. We report the case of median nerve palsy after MiraDry therapy for axillary hyperhidrosis in a thin young man. We recommend using low-energy settings and pre-procedural ultrasound for young, thin patients because of the more superficial course of the brachial plexus within the axilla
The Polarization of the Cosmic Microwave Background Due to Primordial Gravitational Waves
We review current observational constraints on the polarization of the Cosmic
Microwave Background (CMB), with a particular emphasis on detecting the
signature of primordial gravitational waves. We present an analytic solution to
the Polanarev approximation for CMB polarization produced by primordial
gravitational waves. This simplifies the calculation of the curl, or B-mode
power spectrum associated with gravitational waves during the epoch of
cosmological inflation. We compare our analytic method to existing numerical
methods and also make predictions for the sensitivity of upcoming CMB
polarization observations to the inflationary gravitational wave background. We
show that upcoming experiments should be able either detect the relic
gravitational wave background or completely rule out whole classes of
inflationary models.Comment: 25 pages, 4 figures, review published in IJMP
Ternatin and improved synthetic variants kill cancer cells by targeting the elongation factor-1A ternary complex.
Cyclic peptide natural products have evolved to exploit diverse protein targets, many of which control essential cellular processes. Inspired by a series of cyclic peptides with partially elucidated structures, we designed synthetic variants of ternatin, a cytotoxic and anti-adipogenic natural product whose molecular mode of action was unknown. The new ternatin variants are cytotoxic toward cancer cells, with up to 500-fold greater potency than ternatin itself. Using a ternatin photo-affinity probe, we identify the translation elongation factor-1A ternary complex (eEF1A·GTP·aminoacyl-tRNA) as a specific target and demonstrate competitive binding by the unrelated natural products, didemnin and cytotrienin. Mutations in domain III of eEF1A prevent ternatin binding and confer resistance to its cytotoxic effects, implicating the adjacent hydrophobic surface as a functional hot spot for eEF1A modulation. We conclude that the eukaryotic elongation factor-1A and its ternary complex with GTP and aminoacyl-tRNA are common targets for the evolution of cytotoxic natural products
Assessing Client Progress Session by Session in the Treatment of Social Anxiety Disorder: The Social Anxiety Session Change Index
Frequent assessment during therapy can improve treatments and provide accountability. However, clinicians often do not monitor progress because of the time it takes to administer and score assessments. In response, the Social Anxiety Session Change Index (SASCI) was developed. The SASCI is a short, easily administered rating of subjective improvement that asks clients with social anxiety disorder how much they have changed since the beginning of therapy. Change on the SASCI was related to change in fear of negative evaluation, a core aspect of social anxiety, and to clinician-rated improvement, but not to ratings of anxiety sensitivity or depression. Because it is brief and easily interpretable, the SASCI can be used in a variety of clinical settings to monitor change across therapy. The SASCI is presented along with examples of how the information gathered from frequent administration can inform clinical practice
Rapid pathogen-specific phenotypic antibiotic susceptibility testing using digital LAMP quantification in clinical samples
Rapid antimicrobial susceptibility testing (AST) is urgently needed for informing treatment decisions and preventing the spread of antimicrobial resistance resulting from the misuse and overuse of antibiotics. To date, no phenotypic AST exists that can be performed within a single patient visit (30 min) directly from clinical samples. We show that AST results can be obtained by using digital nucleic acid quantification to measure the phenotypic response of Escherichia coli present within clinical urine samples exposed to an antibiotic for 15 min. We performed this rapid AST using our ultrafast (~7 min) digital real-time loop-mediated isothermal amplification (dLAMP) assay [area under the curve (AUC), 0.96] and compared the results to a commercial (~2 hours) digital polymerase chain reaction assay (AUC, 0.98). The rapid dLAMP assay can be used with SlipChip microfluidic devices to determine the phenotypic antibiotic susceptibility of E. coli directly from clinical urine samples in less than 30 min. With further development for additional pathogens, antibiotics, and sample types, rapid digital AST (dAST) could enable rapid clinical decision-making, improve management of infectious diseases, and facilitate antimicrobial stewardship
Genetic associations of nonsynonymous exonic variants with psychophysiological endophenotypes
We mapped ∼85,000 rare nonsynonymous exonic single nucleotide polymorphisms ( SNPs ) to 17 psychophysiological endophenotypes in 4,905 individuals, including antisaccade eye movements, resting EEG , P 300 amplitude, electrodermal activity, affect‐modulated startle eye blink. Nonsynonymous SNPs are predicted to directly change or disrupt proteins encoded by genes and are expected to have significant biological consequences. Most such variants are rare, and new technologies can efficiently assay them on a large scale. We assayed 247,870 mostly rare SNPs on an Illumina exome array. Approximately 85,000 of the SNPs were polymorphic, rare ( MAF < .05), and nonsynonymous. Single variant association tests identified a SNP in the PARD 3 gene associated with theta resting EEG power. The sequence kernel association test, a gene‐based test, identified a gene PNPLA 7 associated with pleasant difference startle, the difference in startle magnitude between pleasant and neutral images. No other single nonsynonymous variant, or gene‐based group of variants, was strongly associated with any endophenotype.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109617/1/psyp12349.pd
CMBPol Mission Concept Study: Gravitational Lensing
Gravitational lensing of the cosmic microwave background by large-scale
structure in the late universe is both a source of cosmological information and
a potential contaminant of primordial gravity waves. Because lensing imprints
growth of structure in the late universe on the CMB, measurements of CMB
lensing will constrain parameters to which the CMB would not otherwise be
sensitive, such as neutrino mass.
If the instrumental noise is sufficiently small (<~ 5 uK-arcmin), the
gravitational lensing contribution to the large-scale B-mode will be the
limiting source of contamination when constraining a stochastic background of
gravity waves in the early universe, one of the most exciting prospects for
future CMB polarization experiments. High-sensitivity measurements of
small-scale B-modes can reduce this contamination through a lens reconstruction
technique that separates the lensing and primordial contributions to the B-mode
on large scales.
A fundamental design decision for a future CMB polarization experiment such
as CMBpol is whether to have coarse angular resolution so that only the
large-scale B-mode (and the large-scale E-mode from reionization) is measured,
or high resolution to additionally measure CMB lensing. The purpose of this
white paper is to evaluate the science case for CMB lensing in polarization:
constraints on cosmological parameters, increased sensitivity to the gravity
wave B-mode via lens reconstruction, expected level of contamination from
non-CMB foregrounds, and required control of beam systematics
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