Due to these efforts and the costs of the analyses, serial sampling is feasible in an experimental setting, but not for measurements on a routine basis. The present study focuses on the feasibility of an innovative, noninvasive spectroscopic technique that allows in vivo measurements of carotenoids in the skin by reflection spectroscopy. To this end, in a first trial, repeated measurements of the carotenoid

concentration of the udder skin were performed on 25 healthy cattle from different breeds. Carotenoid concentrations showed Ispinesib in vivo highly significant differences between individual animals (P < 0.001), although they were kept under the same environmental conditions and received the same diet. The carotenoid concentrations in “sensitive” and “robust” cows (evaluated by a temperament test) differed significantly (P < 0.005), with higher concentrations observed in robust cows. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.JBO.17.10.101514]“
“Background: The only published US study,

on racial/ethnic disparities in inpatient asthma management was performed in 1989-1990 at a single center. The authors reported that black and Hispanic children were provided substandard care at hospital discharge compared to white children. The purpose of the present analysis was to reexamine this important issue in a large multicenter study.\n\nMethods: Wnt assay A cohort study of 1,232 children and adults hospitalized with a physician diagnosis of acute asthma at 30 hospitals in 22 US states was used.\n\nResults: The cohort included 562 children (age range, 2 to 17 years; 39% white; 42% black; and 19% Hispanic) and 670 adults (age range, 18 to 54 years; 44% white; 44% black; and 12% Hispanic). There were no significant

racial/ethnic differences in the choice of inpatient medications or length of stay among either children or adults. At hospital discharge, Hispanic children were less likely to receive an asthma action plan (37%) compared to white children (60%) or black children (63%; p < 0.001). Multivariate adjustment for eight variables (including socioeconomic status, hospital admissions for asthma in the past year, medication use prior to presentation, physical examination findings, selleck chemical and hospital admission location) attenuated the statistical significance of this association (odds ratio, 0.5; 95% confidence interval, 0.1 to 2.5).\n\nConclusions: We did not identify racial/ethnic disparities in the inpatient treatment and outcomes for children or adults with acute asthma. At hospital discharge, Hispanic children were less likely to receive an asthma action plan compared to white or black children, possibly due to language or socioeconomic differences. (CHEST 2009; 135:1527-1534)”
“Background: Pooling is a cost effective way to collect data for genetic association studies, particularly for rare genetic variants.

Conclusions: PIVKA-II is useful for determining patient survival and the risk of recurrence in modified UICC T3 stage HCC patients.”
“Background. There is evidence to support that nutritional deficiency can reduce the body’s immune function,

thereby decreasing resistance to Fedratinib mouse disease and increasing susceptibility to intestinal parasites. Methods. A cross-sectional survey was carried out on 693 school-aged children from 5 schistosomiasis-endemic villages in Northern Samar, the Philippines. Data on dietary intake, nutritional status, and intestinal parasitic infection were collected. Results. The prevalence of stunting, thinness, and wasting was 49.2%, 27.8%, and 59.7% of all children. The proportion of children infected with Schistosoma japonicum (15.6%, P = .03) and

SB203580 hookworm (22.0%, P = .05) were significantly lower among children who met the recommended energy and nutrient intake (RENI) for total calories. The percentage of children infected with Trichuris trichiura was highest among children who did not meet the RENI for energy (74.1%, P = .04), iron (73.4%, P = .01), thiamine (74.0%, P = .00), and riboflavin (73.3%, P = .01). Susceptibility to having 1 or more parasitic infections was significantly associated with poor intake of energy (P = .04), thiamine (P = .02), and riboflavin (P = .01). The proportion of stunted children was significantly higher among children who did not meet the RENI for energy (68.9%, P = .002), protein (54.0%, P = .004), or niacin (30.8%, P = .02) and for those infected with hookworm (31.8%, P = .0002). After adjusting for potential confounders, protein intake less than the RENI (odds ratio [OR], 1.48; 95% confidence interval [CI], 1.03-2.14), and hookworm infection (OR, 1.77; 95% CI, 1.22-2.55) were the major predictors of stunting. Conclusions. The results support the hypothesis that poor nutrient intake may increase susceptibility to parasitic diseases and together Baf-A1 supplier they negatively affect childhood nutritional

status.”
“The regulation of mammalian myocardial carbohydrate metabolism is complex; many factors such as arterial substrate and hormone levels, coronary flow, inotropic state and the nutritional status of the tissue play a role in regulating mammalian myocardial carbohydrate metabolism. The Pyruvate Dehydrogenase Complex (PDHc), a mitochondrial matrix multienzyme complex, plays an important role in energy homeostasis in the heart by providing the link between glycolysis and the tricarboxylic acid (TCA) cycle. In TCA cycle, PDHc catalyzes the conversion of pyruvate into acetyl-CoA. This review determines that there is altered cardiac glucose in various pathophysiological states consequently causing PDC to be altered.

The phenol-sulfuric acid method Pfizer Licensed Compound Library was used to quantify polysaccharides, and the monosaccharide composition of the polysaccharides was determined by gas chromatography. Stepwise discriminant analysis was used to differentiate among the five closely related species based on the chemical composition analysis. This proved to be a simple and accurate approach for discriminating among these species. The results also showed that the polysaccharide content, the amounts of the four low molecular weight compounds, and the mannose to glucose ratio,

were important factors for species discriminant. Therefore, we propose that a chemical analysis based on quantification of naringenin, bibenzyl, and polysaccharides is effective for identifying D. officinale.”
“Objective. The authors performed phase I/II clinical trial to evaluate the toxicity and efficacy of carbon ion radiotherapy (C-ion RT) for locally advanced squamous cell carcinoma of the uterine cervix.\n\nMethods. Between April 2000 and January 2006, 22 patients for Protocol 9902 were treated with C-ion RT.

The number of patients with stage IIB, VX-770 solubility dmso IIIB, and IVA diseases was 1, 18, and 3, respectively. All patients had bulky tumors measuring 4.0-12.0 cm (median 6.2 cm). The whole pelvic dose was fixed at 39.0 GyE for 13 fractions, and additional 15.0 GyE for 5 fractions was given to the gross tumor volume (GTV) and surrounding tissues.

With regard to local boost, a dose-escalation study was planned for 2 fractions to GTV. Total see more dose to the cervical tumor was 64.0-72.0 GyE for 20 fractions.\n\nResults. All patients completed the scheduled therapy and no patient developed Grade 2 or higher acute toxicity. There was no Grade 3 or higher late complications at each dose. The 5-year overall survival rate and local control rate were 50.0% and 68.2%, respectively. Seven out of the 16 patients who received 64.0-68.0 GyE developed local recurrences, but all patients who received 72.0 GyE maintained local control.\n\nConclusions. There were no severe acute or late complications in this trial. C-ion RT has the potential to improve the treatment for locally advanced bulky cervical cancer by applying a total dose of 72.0 GyE, with the results lending incentive to further investigations to confirm the therapeutic efficacy. (C) 2013 Elsevier Inc. All rights reserved.”
“We studied the dose-dependent cardiotoxic effect of propranolol. Intraperitoneal injection of propranolol in doses of 1 and 2 mg/100 g body weight produced a potent effect on central hemodynamics and myocardial contractility, impaired diastolic relaxation, and caused damage to cardiomyocyte membranes due to activation of free radical oxidation.

To better define the physiological properties of NG2(+) cells, we used transgenic mice that allowed an unbiased sampling of this population and unambiguous identification of cells in discrete states of differentiation. Using acute brain slices prepared from developing and mature mice, we found that NG2(+) cells in diverse brain regions share a core set of physiological properties, including expression of voltage-gated Na(+) (NaV) channels and ionotropic glutamate receptors, and formation of synapses with glutamatergic neurons. Although small amplitude Na(+) spikes could be elicited in some NG2(+) cells during the first postnatal week, they were not capable of generating action potentials. Transition of these

progenitors to the premyelinating stage was accompanied by VX-770 research buy LY2606368 the rapid removal of synaptic input, as well as downregulation of AMPA and NMDA receptors and NaV channels. Thus, prior reports of physiological heterogeneity among NG2(+) cells may reflect analysis of cells in later stages of maturation. These results suggest that NG2(+) cells are uniquely positioned within the oligodendrocyte lineage to monitor the firing patterns of surrounding neurons.”
“Cellulase was immobilized on chitosan by the method of covalent binding. The optimum immobilized conditions were as follow: the pH value was 5.0, the glutaraldehyde concentration was 0.015 (w/v) and the formaldehyde concentration was 0.15 (w/v). Both the free

and immobilized cellulase were characterized by determining the pH, temperature, thermal stability and storage stability. The optimum pH of both the free and immobilized cellulase was found as 4. The immobilized cellulase had optimum temperature of 50 degrees C as compared to 40 degrees C in case of free enzyme. The immobilized enzyme showed higher thermal stability than the free cellulase, after 120 min, the this website activity of immobilized cellulose and the free enzyme retained 86.5 and 61%

respectively. After 11 cycles, the activity of the immobilize enzyme conserved 80.27%. The immobilized enzyme exhibited slightly better storage stability than the free enzyme. The Km and Vm values for the immobilized and free cellulase were 8.1 and 1.84 mg/L and 0.01 and 0.0036 mg/ml/min respectively. Cellulose hydrolysis by immobilized cellulase in the presence of a 88 ionic liquid (IL), 1,3-dimethylimidazolium dimethylphosphate (MMIM-DMP), was investgated. The result showed that the addition of 20% (v/v) MMIM-DMP gave the highest initial rate, which was 1.3 and 13.9 times higher than the hydrolysis rate in citric acid – sodium hydrogen phosphate buffer and in IL, respectively.”
“Animals are known to exhibit ‘personality’; that is, individual differences in behaviour that are consistent across time and/or situations. One axis of personality of particular importance for behavioural ecology is boldness, which can be defined as the tendency of an individual to take risks.

(Fertil Steril(R) 2010;94:574-80. (C) 2010 by American Society for Reproductive Medicine.)”
“Here we have developed protocols using the baboon as a complementary alternative Old World Primate to rhesus and other macaques which have severe limitations in their availability. Baboons are not limited

as research resources, they are evolutionarily closer to humans, and the multiple generations of pedigreed colonies which display complex human disease phenotypes all support their further optimization as an invaluable primate model. Since neither baboon-assisted reproductive technologies nor baboon embryonic stem cells (ESCs) have been reported, here we describe the first derivations and characterization of baboon ESC lines from IVF-generated blastocysts. Two ESCs lines (BabESC-4 and BabESC-15) SN-38 research buy display ESC morphology, express pluripotency markers (Oct-4, hTert, Nanog, Sox-2, Rex-1, TRA1-60, Alvespimycin chemical structure TRA1-81), and maintain stable euploid female karyotypes with parentage confirmed independently. They have been grown continuously for >430 and

290 days, respectively. Teratomas from both lines have all three germ layers. Availabilities of these BabESCs represent another important resource for stem cell biologists. (C) 2009 Elsevier B.V. All rights reserved.”
“Our study is to investigate whether tyrosine kinase receptor B (TrkB) is expressed in eutopic endometrium of women with adenomyosis and its association with clinical characteristics.\n\nWe collected endometrial tissues from 31 women with adenomyosis and 30 adenomyosis-free women undergoing surgery for benign indications. TrkB expression was assessed by immunohistochemistry and reverse-transcription polymerase chain reaction.\n\nImmunoreactive staining for TrkB was present as brown flocculent precipitate in the endometrial cells. The average level of TrkB protein (quantitation STI571 mw of immunostaining intensity) in secretory endometrial samples of women with adenomyosis was significantly higher than that in controls (p < 0.01). The average level of TrkB messenger RNA (mRNA) expression of women with adenomyosis was significantly

higher than that of controls at secretory phase (p < 0.01). In addition, the immunostaining quantitation of TrkB protein was positively correlated with the serum CA125 (r = 0.308, p = 0.016) and dysmenorrhea (r = 0.393, p = 0.002).\n\nOur study revealed elevation of TrkB protein and mRNA expression in the secretory endometrium of women with adenomyosis. Moreover, TrkB protein expression in human endometrium was positively correlated with the serum CA125 and dysmenorrhea. TrkB might contribute to the pathogenesis and progression of adenomyosis.”
“Ubiquinone-10 (CoQ10), a vitamin-like lipophilic component of the membrane-bound electron transport system, has a wide range of therapeutic, neutraceutical, and cosmeceutical applications.

Conduction mechanism in the freeze-out regime has been discussed. Analysis of the admittance peak, E1 together with the characteristic features in the frequency dependence of the conduction in freeze out regime suggest that conduction properties of the n-GaInNAsSb material in the freeze-out condition is governed by Mott’s variable range hopping mechanism. (C) 2012 American Institute of Physics. [http://0-dx.doi.org.brum.beds.ac.uk/10.1063/1.4768716]“
“A detailed study of the difference in reactivity of the copolymerization reactions of styrene oxide vs.

propylene oxide with carbon dioxide utilizing binary (salen) cobalt(III) catalyst systems to provide perfectly alternating copolymers is reported. APR-246 molecular weight This investigation focuses on the discrepancy exhibited by these two terminal epoxides for the preference for C-O bond cleavage during the ring-opening process. It was found that the nucleophilic ring-opening of styrene oxide occurs predominantly PND-1186 purchase at the methine C-alpha-O bond which leads to an inversion of configuration at the methine carbon center. This tendency results in a significantly lower reactivity as well as a deterrent for synthesizing stereoregular poly(styrene carbonate) when compared to the propylene

oxide/CO2 process. The chiral environment about the metal center had a notable effect on the regioselectivity of the ring-opening step for styrene oxide, with the methylene C-beta-O bond being preferentially cleaved. Using a binary catalyst system composed of an unsymmetrical (S, S, S)-salenCo(III) complex in conjunction with the onium salt PPNY (PPN = bis(triphenylphosphine) iminium, and Y = 2,4-dinitrophenoxy), a highly regioregular ring-opening step was observed with a concomitant

96% retention of configuration at the methine carbon center.”
“Fragments of 2 coral PF-04929113 research buy species (Acropora nasuta and Pocillopora damicornis), collected from the South China Sea, were incubated for 94 d under controlled conditions of pCO(2) = 389, 700, and 1214 mu atm. Our incubation experiments showed that the net calcification rate of A. nasuta responded negatively to elevated pCO(2) in both short and mid-term incubations. In contrast, the net calcification rate of P. damicornis increased under elevated pCO(2) during the first 17 d, but then returned to background rates. Based on previous models, our modified models showed that the different responses of these 2 coral species depended on the dissolved inorganic carbon (DIC) and pH levels in coral calcifying fluid. In the studied models, the positive responses of coral calcification to higher pCO(2) could be explained by either low DIC due to a higher photosynthesis rate or a stronger H+ pump.

Chorioamnionitis increases the risk and AZD6738 purchase severity of bronchopulmonary dysplasia and persistent pulmonary hypertension in newborns. It is not known whether the timing of exposure to inflammation in utero is an important contributor to the pathogenesis of bronchopulmonary dysplasia. We hypothesized that chronic inflammation would alter the pulmonary air space and vascular development after 70 days of exposure to infection. Pregnant ewes were given intra-amniotic injection of Ureaplasma parvum serovars 3 or 6 at low (2 x 10(4) cfu) or high doses (2 x 10(7) cfu) or media (controls) at 55 days gestational age. Fetuses were delivered at 125 days (term = 150 days). U. parvum was

grown from the lungs of all exposed fetuses, and neutrophils and monocytes were increased in the air spaces. Lung mRNA expression of IL-1 beta and IL-8, but not IL-6, was

modestly increased in U. parvum-exposed fetuses. U. parvum exposure increased surfactant and improved lung gas volumes. The changes in lung inflammation and maturation were independent of serovar or dose. Exposure to U. parvum did not change multiple indices of air space or vascular development. Parenchymal elastin and collagen content were similar between groups. Expression of several endothelial proteins and pulmonary resistance arteriolar media thickness were also not different between groups. We conclude that chronic exposure to U. parvum does not cause sustained effects on air space

or vascular development in premature lambs.”
“As a new potential inflammatory mediator, visfatin plays an important role in inflammation and atherosclerosis. The formation of macrophage-derived foam cells occurs at GSK1210151A inhibitor the early stage of atherosclerosis Selleckchem Tubastatin A and underlies the visible fatty streak. Recent studies have indicated that visfatin may be associated with the development of foam cells, but its exact effect and molecular mechanism remain unknown. This study aims to study the effect of visfatin on foamy cell formation and its underlying molecular mechanism. Visfatin levels were determined in apolipoprotein E (ApoE) knockout (KO) mice on a western diet for 16 weeks. Effects of visfatin in cholesterol accumulation were studied both in vivo and in vitro. The levels of scavenger receptors located in macrophage surface were measured in RAW264.7 cells after treatment with visfatin. Visfatin levels were much higher in ApoE KO mice than that in the control mice. Meanwhile, oxidized low-density lipoprotein induces both visfatin release from RAW264.7 cells and its cellular levels within 24 h. Visfatin promotes lipid accumulation mainly through excessive cholesterol uptake not only in RAW264.7 cells but also in peritoneal macrophages isolated from ApoE KO mice. Furthermore, visfatin induces the activation of scavenger receptors (SR)-A and cluster of differentiation (CD)36, but not that of SR-BI, ATP-binding cassette transporter (ABC)A1, or ABCG1 in RAW264.7 cells.

Experiments with fluorescent dust demonstrate intra- and inter-plant pollen movement by hawk moths. Although this species is adapted for hawk moth pollination, it readily sets fruit via autonomous autogamy when no visits are made. Thus, it is concluded that it is facultatively xenogamous.

Additional support for this conclusion is provided by the pollen to ovule ratio of 1407 and by the fact that the plants grow in a region that has few or no faithful pollinators. Conservation efforts for I. habeliana should include hand pollinations, which could significantly increase seed set. (C) 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160, 11-20.”
“Visual STM of simple features is achieved through interactions between retinotopic LY2090314 visual cortex and a set of frontal and parietal regions. In the present fMRI study, we investigated effective connectivity between central nodes in this network during the different task epochs of a modified delayed orientation discrimination task. Our univariate analyses demonstrate that the inferior frontal junction (IFJ) is preferentially involved in memory encoding, whereas activity in the putative IPI-145 mouse FEFs and anterior intraparietal sulcus (aIPS) remains elevated throughout periods of memory maintenance. We have earlier reported, using the same task, that areas in visual cortex sustain information

about task-relevant stimulus properties during delay intervals [Sneve, M. H., Alnaes, D., Endestad, T., Greenlee, M. W., & Magnussen, S. Visual

short-term memory: Activity supporting encoding and maintenance in retinotopic visual cortex. Neuroimage, 63, 166-178, 2012]. To elucidate the temporal dynamics of the IFJ-FEF-aIPS-visual cortex network during memory operations, we estimated Granger causality ACY-738 molecular weight effects between these regions with fMRI data representing memory encoding/maintenance as well as during memory retrieval. We also investigated a set of control conditions involving active processing of stimuli not associated with a memory task and passive viewing. In line with the developing understanding of IFJ as a region critical for control processes with a possible initiating role in visual STM operations, we observed influence from IFJ to FEF and aIPS during memory encoding. Furthermore, FEF predicted activity in a set of higher-order visual areas during memory retrieval, a finding consistent with its suggested role in top-down biasing of sensory cortex.”
“Chromatin insulators are genetic elements implicated in the organization of chromatin and the regulation of transcription. In Drosophila, different insulator types were characterized by their locus-specific composition of insulator proteins and co-factors. Insulators mediate specific long-range DNA contacts required for the three dimensional organization of the interphase nucleus and for transcription regulation, but the mechanisms underlying the formation of these contacts is currently unknown.

kg(-1).min(-1) Delta LF:HF (mean +/- SE) 0.5 +/- 0.4, P = 0.4, vs. baseline], whereas men exhibited an unfavorable shift in overall cardiac ANS activity in response to Ang II (Delta LF:HF 2.6 +/- 0.2, P = 0.01, vs. baseline; P = 0.02 vs. female response). This imbalance in sympathovagal tone appeared to be largely driven by a withdrawal in cardioprotective vagal activity in response to Ang II challenge [Delta HF normalized

units (nu), -5.8 +/- 2.9, P = 0.01, vs. baseline; P = 0.006 vs. women] rather than an increase in sympathetic Quisinostat activity (Delta LF nu, -4.5 +/- 5.7, P = 0.3, vs. baseline; P = 0.5 vs. women). Premenopausal women maintain cardiac ANS tone in response to Ang II challenge, whereas similarly aged men exhibit an unfavorable shift in cardiovagal activity. Understanding the role of gender in ANS modulation may help guide risk-reduction strategies in high-risk CVD populations.”
“Triggering Selleckchem LY3023414 of the T cell receptor initiates a signaling cascade resulting in the activation of the T cell. These signals are

integrated alongside those resulting from the triggering of other receptors whose function is to modulate the overall response. CD5 is an immunotyrosine-based inhibition motif-bearing receptor that antagonizes the overt T cell receptor activation response by recruiting inhibitory intracellular mediators such as SHP-1, RasGAP, or Cbl. We now propose that the inhibitory effects of CD5 are also mediated by a parallel pathway that functions at the level of inhibition of Fyn, a kinase generally associated with T cell receptor-mediated activation. After CD5 ligation, phosphorylation of the negative regulatory tyrosine (Tyr(531)) of Fyn increases, and this correlates with a substantial reduction in the kinase activity of Fyn and a profound inhibition of ZAP-70 activation. The effect requires the last

23 amino acids of the cytoplasmic domain of the receptor, strongly implying the involvement of a new CD5-interacting signaling or adaptor protein. Furthermore, we show that upon CD5 ligation there is a profound shift in its distribution from the bulk fluid phase to the lipid raft environment, where it associates with Fyn, Lck, and PAG. We suggest that the relocation of CD5, which we also show is capable of forming homodimers, to the proximity of raft-resident molecules selleck compound enables CD5 to inhibit membrane proximal signaling by controlling the phosphorylation and activity of Fyn, possibly by interfering with the disassembly of C-terminal Src kinase (Csk)-PAG-Fyn complexes during T cell activation.”
“Denervation of skeletal muscles results in loss of muscle mass and contractile force. Recent evidence suggests that local immune system activation plays a key role in these processes, but the mechanisms underlying muscle-immune system cross-talk are not understood. The purpose of this study was to address the mechanisms by which muscle responds to denervation and to elucidate the specific role played by FYN in local immune system activation.

Many participants were prompted to seek medical advice by a family member or acquaintance. Having a transient ischaemic attack negatively changed their perception of their health and their quality AZD0530 of life, but some also

viewed it as a positive event that had warned of their stroke risk and enabled them to take up health maintenance measures. Conclusions. Having a transient ischaemic attack permanently changes peoples quality of life and their perception of their health, despite the transience of the symptoms. The ability of people to make positive health changes after a transient ischaemic attack to some extent ameliorates the negative effects of being aware of their heightened stroke risk. Their appreciation of their quality of life may also be enhanced. The transience of the symptoms and lack of knowledge of transient ischaemic attacks lead to delays in seeking medical advice.”
“Objectives: Symptoms of stress velopharyngeal incompetence (SVPI) have been reported by many wind instrument players. The current study was designed to determine (1) if symptoms of SVPI were accompanied by aeromechanical signs of SVPI and (2) if signs of SVPI differed across musical tasks.\n\nDesign:

Participants were studied during a single recording session.\n\nSetting: find more The study was conducted in a university laboratory.\n\nParticipants: Participants were 10 collegiate trombone players. They were separated into two groups: six who reported symptoms of SVPI https://www.selleckchem.com/products/napabucasin.html and four who reported no symptoms.\n\nMain Outcome Measure: Nasal pressure recorded during trombone playing was used to determine velopharyngeal status (open or closed).\n\nResults: None of the participants exhibited an open velopharynx during trombone playing; however, all participants had positive nasal pressure (indicating an open velopharynx) immediately prior to sound onset on at least some of their breath groups. Two participants had positive nasal pressure

prior to the vast majority of their productions and were given biofeedback and instruction to change this behavior.\n\nConclusions: Symptoms of SVPI do not necessarily indicate the presence of a velopharyngeal-nasal leak during wind instrument playing but may reflect awareness of air leaks immediately prior to sound production. Pre-sound velopharyngeal-nasal air leaks may be amenable to behavioral modification by biofeedback and instruction. Nasal pressure measurement (using a nasal cannula) provides a simple, yet powerful, way to identify SVPI.”
“Steroid hormones regulate multiple but distinct aspects of social behaviors. Testosterone (T) has multiple effects on learned courtship song in that it regulates both the motivation to sing in a particular social context as well as the quality of song produced. The neural substrate(s) where T acts to regulate the motivation to sing as opposed to other aspects of song has not been definitively characterized.