The structure and stabilization mechanism of turbulent lifted non-premixed hydrocarbon flames was studied using combined laser imaging techniques. The burner was a simple nozzle with 4 mm ID and 6 mm OD located in a wind tunnel providing uniform surrounding air flow. Two pure fuels were used: methane and propane, and three diluted fuels of methane with 15% nitrogen; propane with 15% nitrogen; and ethylene with 50% nitrogen. The flames showed a definite triple flame structure at the stabilization region at a relatively low velocity. The flame was anchored to a triple point where three reaction zones met. The flow field structure in the low velocity lifted flames was quite similar to that in laminar triple flames. At the stabilization region, the turbulent flame speed was equal to the local flow velocity perpendicular to the flame front. The scaling analysis showed that stabilization occurs in a region where the mean mixture fraction was 1.1 times the stoichiometric value. The flow velocity and the turbulence intensity were nearly constant along that constant mixture fraction surface. The Damköhler number at stabilization turned into a constant at increasing lift-off heights.

The structure and stabilization mechanism of turbulent lifted non-premixed hydrocarbon flames are examined using combined laser imaging techniques. The techniques include Rayleigh scattering, laser induced predissociation fluorescence of OH, LIF of PAH, LIF of CH2O, and planar imaging velocimetry. Two pure fuels are used: methane (CH4) and propane (C3H8), and three diluted fuels of CH4 with 15% nitrogen; C3H8 with 15% nitrogen, and ethylene (C2H4) with 50% nitrogen. Spectroscopic scanning has been conducted for a stoichiometric methane-air flame to ensure that the signal is free from other interferences occurred within the spectral range of the glass filter. The geometrical structure of multi-reaction zones and flow field at the stabilization region are simultaneously measured in 16 hydrocarbon flames. The data reveal the existence of triple flame structure at the stabilization region of turbulent lifted flames. Increasing the jet velocity leads to an increase of the lift-off height and to a broadening of the lift-off region. The flow field structure in the low velocity lifted flames is quite similar to that in laminar triple flames. At the stabilization region, the turbulent flame speed is equal to the local flow velocity perpendicular to the flame front.

The stomatal conductance (gs) of most plant species decreases in response to elevated atmospheric CO2 concentration. This response could have a significant impact on plant water use in a future climate. However, the regulation of the CO2-induced stomatal closure response is not fully understood. Moreover, the potential genetic links between short-term (within minutes to hours) and long-term (within weeks to months) responses of gs to increased atmospheric CO2 have not been explored.We used Arabidopsis thaliana recombinant inbred lines originating from accessions Col-0 (strong CO2 response) and C24 (weak CO2 response) to study short- and long-term controls of gs. Quantitative trait locus (QTL) mapping was used to identify loci controlling short- and long-term gs responses to elevated CO2, as well as other stomata-related traits.Short- and long-term stomatal responses to elevated CO2 were significantly correlated. Both short- and long-term responses were associated with a QTL at the end of chromosome 2. The location of this QTL was confirmed using near-isogenic lines and it was fine-mapped to a 410-kb region. The QTL did not correspond to any known gene involved in stomatal closure and had no effect on the responsiveness to abscisic acid. Additionally, we identified numerous other loci associated with stomatal regulation.We identified and confirmed the effect of a strong QTL corresponding to a yet unknown regulator of stomatal closure in response to elevated CO2 concentration. The correlation between short- and long-term stomatal CO2 responses and the genetic link between these traits highlight the importance of understanding guard cell CO2 signalling to predict and manipulate plant water use in a world with increasing atmospheric CO2 concentration. This study demonstrates the power of using natural variation to unravel the genetic regulation of complex traits.

A B S T R A C T
Introduction. In 2014, the International Society for Sexual Medicine (ISSM) convened a panel of experts to develop
an evidence-based process of care for the diagnosis and management of testosterone deficiency (TD) in adult men.
The panel considered the definition, epidemiology, etiology, physiologic effects, diagnosis, assessment and treatment
of TD. It also considered the treatment of TD in special populations and commented on contemporary controversies
about testosterone replacement therapy, cardiovascular risk and prostate cancer.
Aim. The aim was to develop clearly worded, practical, evidenced-based recommendations for the diagnosis and
treatment of diagnosis and management of TD for clinicians without expertise in endocrinology, such as physicians
in family medicine and general urology practice.
Method. A comprehensive literature review was performed, followed by a structured, 3-day panel meeting and
6-month panel consultation process using electronic communication. The final guideline was compiled from reports
by individual panel members on areas reflecting their special expertise, and then agreed by all through an iterative
process.
Results. This article contains the report of the ISSM TD Process of Care Committee. It offers a definition of TD
and recommendations for assessment and treatment in different populations. Finally, best practice treatment
recommendations are presented to guide clinicians, both familiar and unfamiliar with TD.
Conclusion. Development of a process of care is an evolutionary process that continually reviews data and incorporates
the best new research. We expect that ongoing research will lead to new insights into the pathophysiology
of TD, as well as new, efficacious and safe treatments. We recommend that this process of care be reevaluated and
updated by the ISSM in 4 years. Dean JD, McMahon CG, Guay AT, Morgentaler A, Althof SE, Becher EF,
Bivalacqua TJ, Burnett AL, Buvat J, El Meliegy A, Hellstrom WJG, Jannini EA, Maggi M, McCullough A,
Torres LO, and Zitzmann M. The International Society for Sexual Medicine’s process of care for the
assessment and management of testosterone deficiency in adult men. J Sex Med 2015;12:1660–1686.

We report on the 1st case of ischemic priapism secondary to poorly controlled homocystinuria. Homocystinuria is a rare, autosomal recessive, inherited disorder of metabolism that is caused by a deficiency of cystathionine synthase, leading to marked hyperhomocysteinemia. Arterial and/or venous thromboemboli are a major cause of mortality and morbidity in patients with homocystinuria. Untreated patients have a 50% chance of having a vascular event by 30 years of age. Increased homocysteine levels have been reported to upregulate prothrombotic factors and downregulate antithrombotic factors; in particular, increased homocystinuria has been found to downregulate nitric oxide (NO). Mice that are deficient in NO synthase in the cavernosal smooth muscles have a higher incidence of priapism. Decrease in NO synthase causes downregulation of cyclic guanosine monophosphate, phosphodiesterase type 5A, and Rho A/Rho-kinase. Because persistently increased homocysteine also downregulates NO, a similar mechanism could be proposed for priapism secondary to homocystinuria. In patients presenting with priapism, specific features of homocystinuria should be sought; in selected patients, screening with plasma total homocysteine might be appropriate. Ischemic priapism secondary to homocystinuria appears to respond well to the standard treatment options of aspiration, intracavernosal injection with phenylephrine, and, if required, a shunting procedure. Johnson M, Murphy E, Raheem A, Ralph D. Poorly Controlled Homocystinuria: A Rare Cause of Ischemic Priapism? Sex Med 2018;6:171-173.

OBJECTIVES: Total annual costs for syncope-related hospitalizations were $2.4 billion in 2000. The aim of this study was to examine the type and number of tests ordered for patients admitted with syncope and whether these tests helped establish the cause.

METHODS: We studied the records of 1038 patients coded as "syncope" in billing records, and 167 fulfilled the eligibility criteria. The main outcome measures were the diagnostic yield of the ordered tests, the incremental cost/incremental benefit, and the number of admissions that can be averted if risk stratification were used in the evaluation.

RESULTS: The etiology of the syncope was identified in 48.3% of the patients. Postural blood pressure measurement has the highest diagnostic yield at 58.7%, whereas history taking diagnosed 19.7% of cases. The diagnostic yields of telemetry, electrocardiogram, radionuclide stress test, echocardiography, and troponin measurement were 4.76%, 4.24%, 3.44%, 0.94%, and 0.62%, respectively. Chest x-ray, carotid ultrasonography, 24-hour Holter monitoring, brain computed tomography, and brain magnetic resonance imaging did not yield the diagnosis in any of the patients. Only 1.9% of the money spent in the evaluation of syncope was effective in leading to a definitive diagnosis. The orthostatic blood pressure measurement was ranked first in the incremental cost/incremental benefit ratio and the radionuclide stress test was ranked last (17.03 vs 42,369.0, respectively). Approximately 6% of the patients did not meet the admission criteria.

CONCLUSIONS: Physicians ordered unnecessary tests that have a low yield and are not cost-effective. A standardized algorithmic approach should be the cornerstone in the evaluation of syncope.

We recently reported that the aldehyde residue of an abasic (Ap) site in duplex DNA can generate an interstrand cross-link via reaction with a guanine residue on the opposing strand. This finding is intriguing because the highly deleterious nature of interstrand cross-links suggests that even small amounts of Ap-derived cross-links could make a significant contribution to the biological consequences stemming from the generation of Ap sites in cellular DNA. Incubation of 21-bp duplexes containing a central 5′-CAp sequence under conditions of reductive amination (NaCNBH3, pH 5.2) generated much higher yields of cross-linked DNA than reported previously. At pH 7, in the absence of reducing agents, these Ap-containing duplexes also produced cross-linked duplexes that were readily detected on denaturing polyacrylamide gels. Cross-link formation was not highly sensitive to reaction conditions, and the cross-link, once formed, was stable to a variety of workup conditions. Results of multiple experiments including MALDI-TOF mass spectrometry, gel mobility, methoxyamine capping of the Ap aldehyde, inosine-for-guanine replacement, hydroxyl radical footprinting, and LC–MS/MS were consistent with a cross-linking mechanism involving reversible reaction of the Ap aldehyde residue with the N2-amino group of the opposing guanine residue in 5′-CAp sequences to generate hemiaminal, imine, or cyclic hemiaminal cross-links (7–10) that were irreversibly converted under conditions of reductive amination (NaCNBH3/pH 5.2) to a stable amine linkage. Further support for the importance of the exocyclic N2-amino group in this reaction was provided by an experiment showing that installation of a 2-aminopurine-thymine base pair at the cross-linking site produced high yields (15–30%) of a cross-linked duplex at neutral pH, in the absence of NaCNBH3.