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The dust emission scheme of Shao (2004) has been implemented into the regional atmospheric model COSMO-ART and has been applied to a severe dust event in northeastern Germany on 8th April 2011. The model sensitivity to soil moisture and vegetation cover has been studied. Soil moisture has been found to be relatively high in the model during the investigation period and has been reduced by different degree to investigate the resulting changes in dust emissions. Two different vegetation datasets have been tested as model input: the climatological vegetation cover data of COSMO-ART (ECOCLIMAP) and the SPOT5 remote sensing vegetation cover data for the time of the event. By varying soil moisture, vegetation cover and by restricting the potential emission area, a set of eleven simulations was generated. Vegetation cover during the event was about 24% lower on average compared to the climatological mean. Thus, dust emissions modeled with SPOT5 vegetation exceeded that modeled with climatological data by a factor of about 5. The modeled dust concentrations were compared with in-situ measurements of aerosol concentration. The temporal evolutions of simulations and observations have significant correlations (0.42–0.85) especially in rural backgrounds. The lower correlations at urban sites are attributed to anthropogenic PM10 sources, which are not included in the model. However, a verification of the magnitude of modeled dust concentrations is not possible due to the uncertainty in soil moisture and emission area. [ABSTRACT FROM AUTHOR]

Objective To assess the prevalence of hypopituitarism following traumatic brain injury (TBI), describe the time-course and assess the association with trauma-related parameters and early post-traumatic hormone alterations. Design A 12-month prospective study. Patients Forty-six consecutive patients with TBI (mild: N = 22; moderate: N = 9; severe: N = 15). Measurements Baseline and stimulated hormone concentrations were assessed in the early phase (0–12 days post-traumatically), and at 3, 6 and 12 months postinjury. Pituitary tests included the Synacthen-test (acute +6 months) and the insulin tolerance test (ITT) or the GHRH + arginine test if the ITT was contraindicated (3 + 12 months). Insufficiencies were confirmed by retesting. Results Early post-traumatic hormone alterations mimicking central hypogonadism or hypothyroidism were present in 35 of the 46 (76%) patients. Three months post-traumatically, 6 of the 46 patients failed anterior pituitary testing. At 12 months, one patient had recovered, whereas none developed new insufficiencies. All insufficient patients had GH deficiency (5 out of 46), followed by ACTH- (3 out of 46), TSH- (1 out of 46), LH/FSH- (1 out of 46) and ADH deficiency (1 out of 46). Hypopituitary patients had more frequently been exposed to severe TBI (4 out of 15) than to mild or moderate TBI (1 out of 31) ( P = 0·02). Early endocrine alterations including lowered thyroid and gonadal hormones, and increased total cortisol, free cortisol and copeptin were positively associated to TBI severity ( P < 0·05), but not to long-term development of hypopituitarism ( P > 0·1), although it was indicative in some. Conclusion Long-term hypopituitarism was frequent only in severe TBI. During the 3–12 months follow-up, recovery but no new insufficiencies were recorded, indicating manifest hypothalamic or pituitary damage already a few months postinjury. Very early hormone alterations were not associated to long-term post-traumatic hypopituitarism. Clinicians should, nonetheless, be aware of potential ACTH deficiency in the early post-traumatic period. [ABSTRACT FROM AUTHOR]

Addition of rice straw, which is a common practice in rice agriculture, generally results in enhanced production and emission of the greenhouse gas methane (CH4). However, it is unclear whether straw addition affects only the activity or also the composition of the methanogenic microbial community. It is also unclear to what extent methanogenic archaea would be able to proliferate in the soil. Anoxic slurries of Italian rice-field soil produced CH4 after a lag, during which ferric iron and sulfate were reduced. Addition of rice straw slightly decreased this lag and greatly enhanced the subsequent production of CH4. At the same time, addition of rice straw enhanced the intermediate production of H2 and acetate that served as the methanogenic substrates. Compared with the unamended control, the addition of rice straw resulted in an increased concentration of phospholipid fatty acids in the soil. Quantitative ‘real-time’ PCR targeting the 16S rRNA gene also showed increased copy numbers of both Bacteria and Archaea in the straw-amended soil at the end of the experiment. The composition of the archaeal community was followed over time by terminal restriction length polymorphism (T-RFLP) analysis of the archaeal 16S rRNA genes extracted from straw-amended soil and the control. Rice Cluster-I (RC-I) methanogens and Methanosarcinaceae were the most abundant methanogenic populations, followed by Methanobacteriales, Methanomicrobiales and Methanosaetaceae. Addition of rice straw resulted in a relative increase of Methanosarcinaceae and Methanobacteriales and a relative decrease of RC-I methanogens and Methanomicrobiales. Our results revealed a dynamic methanogenic community in anoxic rice-field soil and showed that addition of organic matter selectively enhanced the growth of particular methanogenic populations, which were apparently better adapted to the presence of straw than the others. The extent of archaeal growth was consistent with that expected theoretically from the ambient Gibbs free energies of hydrogenotrophic and acetoclastic methanogenesis. [ABSTRACT FROM AUTHOR]

Background Assessment of the hypothalamic–pituitary–adrenal (HPA) axis after pituitary surgery is important for appropriate decision making regarding replacement therapy. The synacthen test is often used but is questioned, as time has to elapse for adrenal atrophy to develop. Objective To audit the use of the 250 µg synacthen test after transsphenoidal adenomectomy. Methods A retrospective study of 110 patients submitted to first-time transsphenoidal adenomectomy. Anterior pituitary testing was performed preoperatively, 1 week and 1, 3, 6 and 12 months postoperatively. The adrenocortical function was tested by a synacthen test (250 µg synacthen i.v.). Results Thirty-two out of 71 patients with normal HPA function before surgery developed insufficiency postoperatively, seven patients presenting an insufficient test response after 1 week, 16 after 1 month and nine after 3 months, whereas none became insufficient during the remaining follow-up. Three patients presented symptomatic adrenal insufficiency during the first postoperative week despite a normal test. All of these developed an insufficient test 1 month postoperatively. A 1-week basal plasma cortisol > 400 nmol/l indicated HPA sufficiency, whereas a basal cortisol ≤ 100 nmol/l indicated insufficiency when related to the diagnosis based on the 3-month synacthen test. Conclusion This study confirms that the synacthen test is of limited use in the early postoperative phase, because out of 62 patients with normal 1-week postoperative synacthen responses, 23 patients developed a test that was indicative of adrenal insufficiency over 1–3 months. Our results indicate that a large proportion of patients should be considered for hydrocortisone replacement therapy up to 3 months postoperatively followed by reassessment of the HPA axis. [ABSTRACT FROM AUTHOR]

Summary Background and aims: Epidemiological studies throughout the world consistently reported higher rates of depression and anxiety disorders in women, whereas men consistently show higher rates of substance and antisocial disorders. The present study examined factors potentially contributing to these gender differences using general population data. Methods: The sample was drawn from population registries (N=4181) and can be regarded as representative for the adult German population aged 18–65. Mental disorders (DSM-IV) were assessed with a diagnostic interview (CIDI) carried out by clinically trained interviewers. A range of sociodemographic variables was analysed within men, within women, and between genders. Results: The prevalence of common mental disorders (mood, anxiety, substance use and somatoform disorders) is higher among females, with the exception of substance use disorders. Young age was related to substance disorders both in women and in men. Not being married and being unemployed were associated with increased rates of mental disorders in both sexes, but in men stronger than in women. Being retired was associated with depression only in women, whereas belonging to a higher social class, working fulltime and having children appeared to be protective factors for men only. Other sociodemographic factors (concerning education, employment and family status) were not associated with increased rates of mental disorders both in women and men. Conclusion: Overall the emotional advantages or disadvantages of marital status, employment status, number of children, parenthood and social class apply equally to men and women. We cannot explain the female preponderance in most mental disorders by detecting specific unfavourable patterns of sociodemographic correlates, suggesting that determinants of gender differences in common mental disorders are still far from being understood. [ABSTRACT FROM AUTHOR]

The purpose of this retrospective study was to elucidate the value of an ACTH assay with high detectability to differentiate between ACTH-dependent and -independent Cushing's syndrome. The study was based on the case records of 56 patients with Cushing's syndrome comprising 34 patients with ACTH-dependent Cushing's syndrome and 22 patients with ACTH-independent Cushing's syndrome. Basal morning plasma 1-39 ACTH was measured using an immunoradiometric assay (IRMA) with a normal range of 1.8-11 pmol/L. Peripheral corticotrophin-releasing hormone (CRH) tests were performed in 24 and 17 patients with ACTH-dependent and -independent Cushing's syndrome, respectively. Using a single ACTH measurement, a complete separation was observed between the two defined groups, with a cut-off value of 2.4 pmol/L. Mean ACTH concentration was 14.4 pmol L (range 2.5-47.7 pmol/L) in ACTH-dependent Cushing's syndrome and 0.6 pmol/L (range 0.2-2.2 pmol/L) in ACTH-independent Cushing's syndrome. The range of separation between the two groups was further increased by using two ACTH measurements in each patient or peripheral stimulation with CRH. It is concluded that in the majority of patients with Cushing's syndrome a single basal morning ACTH determination is sufficient to discriminate between ACTH-dependent and ACTH-independent Cushing's syndrome. In borderline cases with ACTH in the range 2-3 pmol/L, repeated measurements might be necessary. The peripheral CRH test was not superior to repeated ACTH measurements. [ABSTRACT FROM AUTHOR]

N1-coumaroyl spermidine is structurally similar to acylpolyamines found in spider and wasp venoms, which are known to block arthropod glutamate receptors. N1-coumaroyl spermidine reduced the amplitude of excitatory postsynaptic potentials recorded in crayfish muscle. This effect was dose dependent, with an IC50 value of 70 µmol l–1. N1-coumaroyl spermidine reversibly reduced the amplitude of potentials elicited by iontophoretic application of L-glutamate, indicating a direct effect on postsynaptic glutamate receptors. Neither 1 mmol l–1 spermidine nor 1 mmol l–1 coumaric acid altered excitatory postsynaptic potential amplitude, indicating that blockage requires the conjugated phenolic polyamine. N1-coumaroyl spermine, a slightly longer phenolic polyamine, reduced excitatory postsynaptic potential amplitude with approximately the same potency as N1-coumaroyl spermidine. Thus, potency of blockage does not appear to be affected in this experimental preparation by small changes in length of the polyamine. N1-coumaroyl spermidine also reduced excitatory postsynaptic potentials in muscles of the insect Drosophila. The ability of N1-coumaroyl spermidine to attenuate synaptic transmission at insect neuromuscular synapses lends support to the notion that plant-derived phenolic polyamines might serve as natural insecticides. [ABSTRACT FROM AUTHOR]

When cucumber seedlings were dusted with tobacco streak ilarvirus (TSV)-infected pollen and infested with 5-10 thrips (adults and larvae mixed), Thrips tabaci transmitted all three Australian strains of TSV. In similar work, Microcephalothrips abdominalis transmitted both and Frankliniella schultzei one strain, respectively, of two TSV strains tested. Transmission of the Ageratum strain (TSV-Ag) infecting pollen of Ageratum houstonianum was very efficient (100%) by all three thrips species. However, transmission rates of only 0-28% were achieved using the Ajuga strain (TSV-A) and the strawberry strain (TSV- S) in pollen of other hosts. A fourth thrips species, T. parvispinus, transmitted TSV-Ag from infected tomato pollen to Chenopodium amaranticolor seedlings. There was, therefore, little or no vector specificity in the thrips transmission of the three strains of TSV, but factors associated with the virus-infected pollen affected the efficiency of transmission. This is the first report of F. schultzei and T. parvispinus as vectors of TSV. [ABSTRACT FROM AUTHOR]

Describes the necessary role of migrating pioneer neurons and their growth cones in the establishment of peripheral and central pathways in developing nervous systems.

This case study examined student preference for delivery mode of online courses in two graduate degree programs in Library and Information Science. Within-group and between-groups comparisons indicated a distinct preference across the institutions. Findings from focus groups conducted with two cohorts of students enrolled in a federally funded project indicated students preferring asynchronous delivery enrolled in such courses to accommodate busy lifestyles. In the synchronously deployed course, flexibility in accommodation of various learning styles was evidenced by such influential factors as teaching style, instructional design, and topicality. Findings inform online education for modality and instructional style. [ABSTRACT FROM AUTHOR]

Motor activity in healthy young humans displays intrinsic fluctuations that are scale-invariant over a wide range of time scales (from minutes to hours). Human postmortem and animal lesion studies showed that the intact function of the suprachiasmatic nucleus (SCN) is required to maintain such scale-invariant patterns. We therefore hypothesized that scale invariance is degraded in patients treated for suprasellar tumors that compress the SCN. To test the hypothesis, we investigated 68 patients with nonfunctioning pituitary macroadenoma and 22 patients with craniopharyngioma, as well as 72 age-matched healthy controls (age range 21.0-70.6 years). Spontaneous wrist locomotor activity was measured for 7 days with actigraphy, and detrended fluctuation analysis was applied to assess correlations over a range of time scales from minutes to 24 h. For all the subjects, complex scale-invariant correlations were only present for time scales smaller than 1.5 h, and became more random at time scales 1.5-10 h. Patients with suprasellar tumors showed a larger decrease in correlations at 1.5-10 h as compared to healthy controls. Within healthy subject, gender and age >33 year were associated with attenuated scale invariance. Conversely, activity patterns at time scales between 10 and 24 h were significantly more regular than all other time scales, and this was mostly associated with age. In conclusion, scale invariance is degraded in healthy subjects at the ages of >33 year as characterized by attenuation of correlations at time scales 1.5-10 h. In addition, scale invariance was more degraded in patients with suprasellar tumors as compared to healthy subjects. [ABSTRACT FROM AUTHOR]

Particle lifting in dust devils on both Earth and Mars has been studied from many different perspectives, including how dust devils could influence the dust cycles of both planets. Here we review our current understanding of particle entrainment by dust devils by examining results from field observations on Earth and Mars, laboratory experiments (at terrestrial ambient and Mars-analog conditions), and analytical modeling. By combining insights obtained from these three methodologies, we provide a detailed overview on interactions between particle lifting processes due to mechanical, thermal, electrodynamical and pressure effects, and how these processes apply to dust devils on Earth and Mars. Experiments and observations have shown dust devils to be effective lifters of dust given the proper conditions on Earth and Mars. However, dust devil studies have yet to determine the individual roles of each of the component processes acting at any given time in dust devils. [ABSTRACT FROM AUTHOR]

Background: Endophenotypes are heritable markers, which are more prevalent in patients and their healthy relatives than in the general population. Recent studies point at disturbed regulation of the hypothalamic-pituitary-adrenocortical axis as a possible endophenotype for depression. We hypothesize that potential endophenotypes for depression may be affected by selective serotonin re-uptake inhibitor antidepressants in healthy first-degree relatives of depressed patients. The primary outcome measure is the change in plasma cortisol in the dexamethasone-corticotrophin releasing hormone test from baseline to the end of intervention.Methods: The AGENDA trial is designed as a participant, investigator, observer, and data-analyst-blinded randomized trial. Participants are 80 healthy first-degree relatives of patients with depression. Participants are randomized to escitalopram 10 mg per day versus placebo for four weeks. Randomization is stratified by gender and age. The primary outcome measure is the change in plasma cortisol in the dexamethasone-corticotrophin releasing hormone test at entry before intervention to after four weeks of intervention. With the inclusion of 80 participants, a 60% power is obtained to detect a clinically relevant difference in the primary outcome between the intervention and the placebo group. Secondary outcome measures are changes from baseline to four weeks in scores of: 1) cognition and 2) neuroticism. Tertiary outcomes measures are changes from baseline to four weeks in scores of: 1) depression and anxiety symptoms; 2) subjective evaluations of depressive symptoms, perceived stress, quality of life, aggression, sleep, and pain; and 3) salivary cortisol at eight different timepoints during an ordinary day. Assessments are undertaken by assessors blinded to the randomization group. [ABSTRACT FROM AUTHOR]

Genetic manipulation of individual neurons provides a powerful approach toward understanding their contribution to stereotypic behaviors. We describe and evaluate a method for identifying candidate interneurons and associated neuropile compartments that mediate Drosophila larval locomotion. We created Drosophila larvae that express green fluorescent protein (GFP) and a shibire ts1 ( shi ts1) transgene (a temperature-sensitive neuronal silencer) in small numbers of randomly selected cholinergic neurons. These larvae were screened for aberrant behavior at an elevated temperature (31-32°C). Among larvae with abnormal locomotion or sensory-motor responses, some had very small numbers of GFP-labeled temperature-sensitive interneurons. Labeled ascending interneurons projecting from the abdominal ganglia to specific brain neuropile compartments emerged as candidates for mediation of larval locomotion. Random targeting of small sets of neurons for functional evaluation, together with anatomical mapping of their processes, provides a tool for identifying the regions of the central nervous system that are required for normal locomotion. We discuss the limitations and advantages of this approach to discovery of interneurons that regulate motor behavior. [ABSTRACT FROM AUTHOR]

Mice with targeted genetic alterations are the most effective tools for deciphering organismal gene function. We generated an ENU-based parallel C3HeB/FeJ sperm and DNA archive characterized by a high probability to identify allelic variants of target genes as well as high efficiencies in allele retrieval and model revitalization. Our archive size of over 17,000 samples contains approximately 340,000 independent alleles (20 functional mutations per individual sample). Based on an estimated number of approximately 30,000 mouse genes, the parallel sperm/DNA archive should permit the identification and recovery of ten or more alleles per average target gene which translates to a calculated 99% success rate in the discovery of five allelic variants for any given average gene. The low rate of unrelated ENU-induced passenger mutations has no practical impact on the analysis of the allele-specific phenotype at the G3 generation because of dilution and free segregation of such unrelated passenger mutations. To date 39 mouse models representing 33 different genes have been recovered from our archive using in vitro fertilization techniques. The generation time for a murine model heterozygous for a mutation in a gene of interest is less than 2 months, i.e., three to four times faster compared with current embryonic stem-cell–based technologies. We conclude that ENU-based targeted mutagenesis is a powerful tool for the fast and high-throughput production of murine gene-specific models for biomedical research. [ABSTRACT FROM AUTHOR]

The community structure of methanogenic Archaea on anoxically incubated rice roots was investigated by amplification, sequencing, and phylogenetic analysis of 16S rRNA and methyl-coenzyme M reductase (mcrA) genes. Both genes demonstrated the presence of Methanomicrobiaceae, Methanobacteriaceae, Methanosarcinaceae, Methanosaetaceae, and Rice cluster I, an uncultured methanogenic lineage. The pathway of CH4 formation was determined from the 13C-isotopic signatures of the produced CH4, CO2 and acetate. Conditions and duration of incubation clearly affected the methanogenic community structure and the pathway of CH4 formation. Methane was initially produced from reduction of CO2 exclusively, resulting in accumulation of millimolar concentrations of acetate. Simultaneously, the relative abundance of the acetoclastic methanogens (Methanosarcinaceae, Methanosaetaceae), as determined by T-RFLP analysis of 16S rRNA genes, was low during the initial phase of CH4 production. Later on, however, acetate was converted to CH4 so that about 40% of the produced CH4 originated from acetate. Most striking was the observed relative increase of a population of Methanosarcina spp. (but not of Methanosaeta spp.) briefly before acetate concentrations started to decrease. Both acetoclastic methanogenesis and Methanosarcina populations were suppressed by high phosphate concentrations, as observed under application of different buffer systems. Our results demonstrate the parallel change of microbial community structure and function in a complex environment, i.e., the increase of acetoclastic Methanosarcina spp. when high acetate concentrations become available. [ABSTRACT FROM AUTHOR]