39 research outputs found
Quantifying evaporation in the lower atmosphere using machine driven curve fitting to parameterize drop size distributions
Evaporation of hydrometeors in the atmosphere is a process by which liquid water becomes water vapor. Consequences of this process can affect quantitative precipitation forecasts, convective downdrafts quantification, flooding forecasts, and many other forecasting parameters. Accurate and precise forecast modeling often misrepresents this microscale process due to the multiple feedbacks involved, and under- or mis- quantified parameters. Resolving parameters such as the drop size distribution and statistical representation will help to rectify these inadequacies. In this study, multiple observation instruments are used to observe how rain evolves in a dry atmosphere. Instruments include weather balloon radiosondes, laser disdrometers and a vertically pointing micro-rain radar (MRR). These data are then processed using a multitude of modeling methods to best quantify evaporation rates. Several case studies were conducted with the goal of observing and modeling evaporation in a dry layer. Using the MRR and disdrometer data, drop size distributions were observed from the base of the cloud layer to the surface. Calculated liquid water content was used as a parameter to compare the modeled change in water content to the MRR and disdrometer observations. Through this process, a newly developed drop size distribution parameterization using linear regression modeling and a Gaussian distribution mixture was implemented and was shown to be a better method, capturing the larger drops in the distribution. The Gaussian mixture also demonstrated an accurate parameterization in the evaporation quantification when vertical motions were accurately represented. However, accurately quantifying vertical motions using balloon data was problematic in the cases presented and will need to be the subject for future interrogation.Includes bibliographical references
Expansion of Comprehensive Screening of Male Sexually Transmitted Infection Clinic Attendees with \u3cem\u3eMycoplasma genitalium\u3c/em\u3e and \u3cem\u3eTrichomonas vaginalis\u3c/em\u3e Molecular Assessment: a Retrospective Analysis
Of 1,493 encounters of males at a sexually transmitted infection (STI) clinic in a community with a high prevalence of STI, Chlamydia trachomatis was detected in 8.7% and Neisseria gonorrhoeae was detected in 6.6%. Additional Trichomonas vaginalis and Mycoplasma genitalium screening found 17.4% and 23.9% of the encounters, respectively, to be positive for STI. STI agents were detected in 13.7% of urine specimens; addition of pharyngeal and rectal collections to the analysis resulted in detection of STI agents in 19.0% and 23.9% of encounters, respectively. A total of 101 (23.8%) encounters of identified STI involved sole detection of M. genitalium. Expansion of the STI analyte panel (including M. genitalium) and additional specimen source sampling within a comprehensive STI screening program increase identification of male STI carriers
Deterministic Global 3D Fractal Cloud Model for Synthetic Scene Generation
This paper describes the creation of a fast, deterministic, 3D fractal cloud renderer for the AFIT Sensor and Scene Emulation Tool (ASSET). The renderer generates 3D clouds by ray marching through a volume and sampling the level-set of a fractal function. The fractal function is distorted by a displacement map, which is generated using horizontal wind data from a Global Forecast System (GFS) weather file. The vertical windspeed and relative humidity are used to mask the creation of clouds to match realistic large-scale weather patterns over the Earth. Small-scale detail is provided by the fractal functions which are tuned to match natural cloud shapes. This model is intended to run quickly, and it can run in about 700 ms per cloud type. This model generates clouds that appear to match large-scale satellite imagery, and it reproduces natural small-scale shapes. This should enable future versions of ASSET to generate scenarios where the same scene is consistently viewed from both GEO and LEO satellites from multiple perspectives
The FKBP5 Gene Affects Alcohol Drinking in Knockout Mice and Is Implicated in Alcohol Drinking in Humans
FKBP5 encodes FK506-binding protein 5, a glucocorticoid receptor (GR)-binding protein implicated in various psychiatric disorders and alcohol withdrawal severity. The purpose of this study is to characterize alcohol preference and related phenotypes in Fkbp5 knockout (KO) mice and to examine the role of FKBP5 in human alcohol consumption. The following experiments were performed to characterize Fkpb5 KO mice. (1) Fkbp5 KO and wild-type (WT) EtOH consumption was tested using a two-bottle choice paradigm; (2) The EtOH elimination rate was measured after intraperitoneal (IP) injection of 2.0 g/kg EtOH; (3) Blood alcohol concentration (BAC) was measured after 3 h limited access of alcohol; (4) Brain region expression of Fkbp5 was identified using LacZ staining; (5) Baseline corticosterone (CORT) was assessed. Additionally, two SNPs, rs1360780 (C/T) and rs3800373 (T/G), were selected to study the association of FKBP5 with alcohol consumption in humans. Participants were college students (n = 1162) from 21–26 years of age with Chinese, Korean or Caucasian ethnicity. The results, compared to WT mice, for KO mice exhibited an increase in alcohol consumption that was not due to differences in taste sensitivity or alcohol metabolism. Higher BAC was found in KO mice after 3 h of EtOH access. Fkbp5 was highly expressed in brain regions involved in the regulation of the stress response, such as the hippocampus, amygdala, dorsal raphe and locus coeruleus. Both genotypes exhibited similar basal levels of plasma corticosterone (CORT). Finally, single nucleotide polymorphisms (SNPs) in FKBP5 were found to be associated with alcohol drinking in humans. These results suggest that the association between FKBP5 and alcohol consumption is conserved in both mice and humans
Conjunctive input processing drives feature selectivity in hippocampal CA1 neurons
Feature-selective firing allows networks to produce representations of the external and internal environments. Despite its importance, the mechanisms generating neuronal feature selectivity are incompletely understood. In many cortical microcircuits the integration of two functionally distinct inputs occurs nonlinearly through generation of active dendritic signals that drive burst firing and robust plasticity. To examine the role of this processing in feature selectivity, we recorded CA1 pyramidal neuron membrane potential and local field potential in mice running on a linear treadmill. We found that dendritic plateau potentials were produced by an interaction between properly timed input from entorhinal cortex and hippocampal CA3. These conjunctive signals positively modulated the firing of previously established place fields and rapidly induced new place field formation to produce feature selectivity in CA1 that is a function of both entorhinal cortex and CA3 input. Such selectivity could allow mixed network level representations that support context-dependent spatial maps.Howard Hughes Medical InstituteRikagaku Kenkyūjo (Japan
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Science Communication in a Digital Age: Social Media and the American Fisheries Society
Social media platforms are effective tools used
to help communicate and increase involvement in cultural, political,
and scientific circles. In 2012, an ad hoc committee was
established to explore online fisheries science communication
and how social media platforms can be utilized by the American
Fisheries Society (AFS). A survey was disseminated to all AFS
units (chapters, sections, divisions) and student subunits to better
understand the current use of social media within the AFS.
A relatively high response rate (82%) provided some confidence
in the survey results—namely, that nearly 69% or more of units
and subunits used social media. Facebook was the dominant
platform used (59%; all others < 15%) and almost exclusively
(97%) for the purpose of communication. Education, outreach,
and member recruitment were other reasons for social media
use. Finally, whether units currently use social media or not at
all, it was recommended that AFS-led workshops and assistance
would increase the usefulness of social media
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Political warfare and contentious politics
This thesis examines if increased Department of Defense (DOD) involvement in political warfare (PW) is justified through a qualitative, comparative analysis of U.S. PW actions conducted by the Department of State, Central Intelligence Agency, and DOD in two Cold War cases: Italy from 1943–1948 and Chile from 1961–1973. Concepts of strategy and social movement models of Doug McAdam, Charles Tilly, and Sidney Tarrow are applied to historical PW actions, both overt and covert. The case-study analysis clarifies each agency’s conduct of PW and develops analytical tools to classify PW actions by approach and impact within the political setting. Data was collected from archives, declassified government documents, and expert analyses. Results indicate that, compared to other U.S. agencies, the DOD had a limited direct role in PW in the cases studied, but was an important enabler. In applying models of social movement theory to historical analysis, this thesis identifies and develops the contentious politics mobilization model’s potential use in planning and evaluating PW strategies.http://archive.org/details/politicalwarfare1094545947Lieutenant, United States NavyApproved for public release; distribution is unlimited
Dissociation between short-term unloading and resistance training effects on skeletal muscle Na+,K+-ATPase, muscle function, and fatigue in humans
Physical training increases skeletal muscle Na+,K+-ATPase content (NKA) and improves exercise performance, but the effects of inactivity per se on NKA content and isoform abundance in human muscle are unknown. We investigated the effects of 23-day unilateral lower limb suspension (ULLS) and subsequent 4-wk resistance training (RT) on muscle function and NKA in 6 healthy adults, measuring quadriceps muscle peak torque; fatigue and venous [K+] during intense one-legged cycling exercise; and skeletal muscle NKA content ([3H]ouabain binding) and NKA isoform abundances (immunoblotting) in muscle homogenates (α1-3, β1–2) and in single fibers (α1–3, β1). In the unloaded leg after ULLS, quadriceps peak torque and cycling time to fatigue declined by 22 and 23%, respectively, which were restored with RT. Whole muscle NKA content and homogenate NKA α1–3 and β1–2 isoform abundances were unchanged with ULLS or RT. However, in single muscle fibers, NKA α3 in type I (−66%, P = 0.006) and β1 in type II fibers (−40%, P = 0.016) decreased after ULLS, with other NKA isoforms unchanged. After RT, NKA α1 (79%, P = 0.004) and β1 (35%, P = 0.01) increased in type II fibers, while α2 (76%, P = 0.028) and α3 (142%, P = 0.004) increased in type I fibers compared with post-ULLS. Despite considerably impaired muscle function and earlier fatigue onset, muscle NKA content and homogenate α1 and α2 abundances were unchanged, thus being resilient to inactivity induced by ULLS. Nonetheless, fiber type-specific downregulation with inactivity and upregulation with RT of several NKA isoforms indicate complex regulation of muscle NKA expression in humans