An electrocardiogram-based AI algorithm for early detection of pulmonary hypertension.

Background: Early diagnosis of pulmonary hypertension (PH) is critical for effective treatment and management. We aimed to develop and externally validate an artificial intelligence algorithm that could serve as a PH screening tool, based on analysis of a standard 12-lead ECG.

Methods: The PH Early Detection Algorithm (PH-EDA) is a convolutional neural network developed using retrospective ECG voltage-time data, with patients classified as "PH-likely" or "PH-unlikely" (controls) based on right heart catheterisation or echocardiography.

Development and evaluation of a predictive algorithm for unsatisfactory response among patients with pulmonary arterial hypertension using health insurance claims data.

Objective: This study aimed to develop and validate a predictive algorithm for unsatisfactory response to initial pulmonary arterial hypertension (PAH) therapy using health insurance claims.

Methods: Adult patients with PAH initiated on a first PAH therapy (index date) were identified from Optum's de-identified Clinformatics Data Mart Database (1/1/2010-12/31/2019). A random survival forest algorithm was developed using patient-month data and predicted the "survival function" (i.

Burden of pulmonary hypertension in patients with portal hypertension in the United States: a retrospective database study.

Patients with portal hypertension may develop pulmonary hypertension. The economic implications of these comorbidities have not been systematically assessed. We compared healthcare resource utilization and costs in the United States between patients with co-existing portal hypertension and pulmonary hypertension (pulmonary hypertension cohort) and a matched cohort of portal hypertension patients without pulmonary hypertension (control cohort).

State policies about physical activity minutes in physical education or during school.

Background: School policies can change practices on a relatively permanent basis. This study investigated adoption and implementation of state-level policies specifying minutes (or percent) of physical activity in physical education (PE) or during school.

Methods: Policies were identified from existing databases and rated as having weak, moderate, or strong wording.

Engaging school governance leaders to influence physical activity policies.

Background: Most youth are not meeting physical activity guidelines, and schools are a key venue for providing physical activity. School districts can provide physical activity opportunities through the adoption, implementation, monitoring, and evaluation of policies. This paper reports results of a 2009 survey of California school governance leaders on the barriers and opportunities to providing school-based physical activity and strategies to promote adoption of evidence-based policies.

School wellness policies: perceptions, barriers, and needs among school leaders and wellness advocates.

Background: School wellness policies are a key component to the prevention of adolescent obesity. This national research study sought to understand the wellness environment in school districts across the country and to identify challenges districts face and needs they have in order to effectively implement, monitor, and evaluate school wellness policies. The study determined (1) perceptions, barriers, and opportunities regarding the development, implementation, and monitoring/evaluation of school wellness policies among school board members, state school boards association leaders, state public health nutrition directors, and school wellness advocates; (2) the readiness and capacity of survey groups to address nutrition and physical activity policies; (3) the extent to which survey groups collaborate; and (4) the acceptability of wellness tools.

Development of a genetic system for the chemolithoautotrophic bacterium Thiobacillus denitrificans.

Thiobacillus denitrificans is a widespread, chemolithoautotrophic bacterium with an unusual and environmentally relevant metabolic repertoire, which includes its ability to couple denitrification to sulfur compound oxidation; to catalyze anaerobic, nitrate-dependent oxidation of Fe(II) and U(IV); and to oxidize mineral electron donors. Recent analysis of its genome sequence also revealed the presence of genes encoding two [NiFe]hydrogenases, whose role in metabolism is unclear, as the sequenced strain does not appear to be able to grow on hydrogen as a sole electron donor under denitrifying conditions. In this study, we report the development of a genetic system for T.

California school board members' perceptions of factors influencing school nutrition policy.

Enactment and enforcement of school nutrition policies represent key components in adolescent overweight and obesity prevention. This study determined: 1) California school board members' attitudes, perceptions, and motivations related to enactment of policies that support healthy eating in schools; and 2) barriers to adopting school policies that support healthy eating. To understand board members' decision-making process, key informant interviews were conducted and a survey was administered to 404 school board members.

Genome differences that distinguish Bacillus anthracis from Bacillus cereus and Bacillus thuringiensis.

The three species of the group 1 bacilli, Bacillus anthracis, B. cereus, and B. thuringiensis, are genetically very closely related.

Establishment of uncharacterized plasmids in Escherichia coli by in vitro transposition.

We present a simple approach that permits any circular plasmid, such as uncharacterized plasmids from diverse prokaryotes, to be established in Escherichia coli, thereby facilitating subsequent structural and functional studies. An in vitro transposition reaction is used to introduce a well-characterized replicon and selectable marker into purified plasmids, which are then used to transform E. coli.

Use of subtractive hybridization for comprehensive surveys of prokaryotic genome differences.

Comparative bacterial genomics shows that even different isolates of the same bacterial species can vary significantly in gene content. An effective means to survey differences across whole genomes would be highly advantageous for understanding this variation. Here we show that suppression subtractive hybridization (SSH) provides high, representative coverage of regions that differ between similar genomes.

Genome plasticity in Yersinia pestis.

Yersinia pestis, the causative agent of bubonic plague, emerged recently (<20000 years ago) as a clone of Yersinia pseudotuberculosis. There is scant evidence of genome diversity in Y. pestis, although it is possible to differentiate three biovars (antiqua, mediaevalis or orientalis) based on two biochemical tests.

Identification by subtractive hybridization of sequences specific for Salmonella enterica serovar enteritidis.

Salmonella enterica serovar Enteritidis, a major cause of food poisoning, can be transmitted to humans through intact chicken eggs when the contents have not been thoroughly cooked. Infection in chickens is asymptomatic; therefore, simple, sensitive, and specific detection methods are crucial for efforts to limit human exposure. Suppression subtractive hybridization was used to isolate DNA restriction fragments present in Salmonella serovar Enteritidis but absent in other bacteria found in poultry environments.

Oxygen regulation of expression of nitrogen fixation genes in Rhizobium meliloti.

The sensor kinase FixL and the response regulator FixJ induce the expression of the nitrogen fixation genes of Rhizobium meliloti in response to microaerobiosis, which is a characteristic feature of the plant root nodule interior where the bacteria fix nitrogen. The kinase activity of a purified, soluble derivative of the membrane-bound hemoprotein FixL, designated FixL*, is stimulated under low oxygen conditions, thus increasing FixJ-phosphate levels. FixJ-phosphate is a potent transcriptional activator of the nifA and fixK genes, the products of which, in turn, induce the expression of most if not all of the remaining nitrogen fixation genes.

Oxygen regulation of nifA transcription in vitro.

In Rhizobium meliloti, transcription of the key nitrogen-fixation regulatory genes nifA and fixK is induced in response to microaerobiosis through the action of the FixL and FixJ proteins. These two proteins are sensor and regulator homologues, respectively, of a large family of bacterial two-component systems involved in sensing and responding to environmental changes. A soluble, truncated form of the membrane protein FixL, FixL*, has been shown to be a hemoprotein that phosphorylates and dephosphorylates FixJ in response to oxygen tension.

Mutational analysis of the Rhizobium meliloti nifA promoter.

The nifA gene of Rhizobium meliloti, the bacterial endosymbiont of alfalfa, is a regulatory nitrogen fixation gene required for the induction of several key nif and fix genes. Transcription of nifA is strongly induced in planta and under microaerobic conditions ex planta. Induction of nifA, in turn, is positively controlled by the fixL and fixJ genes of R.

Description of a polarized source of He i radiation for surface studies.

A polarized radiation source has been designed and built for use in angular-resolved photoelectron spectroscopy on surfaces of single crystals under ultrahigh vacuum. The light from a discharge in helium is polarized by a triple reflection from a series of gold mirrors, producing a plane-polarized beam of He i radiation (21.22 eV) with a polarization of 80%.

Xenon Tetrafluoride Molecule and Its Thermal Motion: A Neutron Diffraction Study.

A neutron-diffraction analysis of the xenon tetrafluoride crystal structure has confirmed the square-planar symmetry of the molecule; from the data the average Xe to F bond length is 1.953 A (sigma = .002) and the F to Xe to F angle is 90.

Xenon Difluoride and the Nature of the Xenon-Fluorine Bond.

Xenon reacts with fluorine to form XeF(2) which can be isolated before it reacts with fluorine to form XeF(4). The linear configuration of XeF(2) with the 2.00-A bond length and the vibrational force constants support the assignment of 10 electrons to the valence shell of xenon.