A New Distance Stereotest by Autostereoscopic Display Using an Eye-Tracking Method.

Objectives: This research aimed to present a novel glasses-free distance random-dot stereotest system (GFDRDSS) using an eye-tracking method. Methods: A single-view autostereoscopic display applying a backlight control system combined with an eye-tracking method and the corresponding random-dot stereotest software were developed to create a GFDRDSS with a viewing distance of 5 m. The stereoacuity of 12 subjects with normal eye position was evaluated using the Randot Stereotest, Stereoscopic Test Charts vol. 3 (Yan's Charts), Distance Randot® Stereotest, and GFDRDSS. Results: The GFDRDSS could provide distinct and stable glasses-free stereoscopic perception even while the subject was moving their head. It could evaluate binocular disparities of 40-2,400 arcsec. Eleven subjects with normal near visual acuity had fine near stereovision (20-60 arcsec) using the Randot stereotest and Yan's Charts. Under refractive correction, 10 subjects had fine stereovision (≤60 arcsec) using the GFDRDSS at a distance of 5 m, and 9 had fine stereovision using the Distance Randot® Stereotest at 3 m. Other subjects described the 100 arcsec-level stereograms correctly. The results exhibited a concordance of stereoacuity within one degrade between the two distance stereotests. Conclusion: The proposed GFDRDSS can alternately project a couple of random-dot stereograms to the subjects' eyes and provide a glasses-free distance stereotest, which showed good concordance with the Distance Randot® Stereotest. More data are needed for statistical studies.

A new stem-varanid lizard (Reptilia, Squamata) from the early Eocene of China.

Monitor lizards (genus Varanus) are today distributed across Asia, Africa and Australasia and represent one of the most recognizable and successful lizard lineages. They include charismatic living species like the Komodo dragon of Indonesia and the even larger extinct Varanus prisca (Megalania) of Australia. The fossil record suggests that living varanids had their origins in a diverse assemblage of stem (varaniform) species known from the Late Cretaceous of China and Mongolia. However, determining the biogeographic origins of crown-varanids has proved problematic, with Asia, Africa and Australia each being proposed. The problem is complicated by the fragmentary nature of many attributed specimens, and the fact that the most widely accepted, and most complete, fossil of a stem-varanid, that of Saniwa ensidens, is from North America. In this paper, we describe a well-preserved skull and skeleton of a new genus of stem-varanid from the Eocene of China. Phylogenetic analysis places the new genus as the sister taxon of Varanus, suggesting that the transition from Cretaceous varaniform lizards to Varanus occurred in East Asia before the origin and dispersal of Varanus to other regions. The discovery of the new specimen thus fills an important gap in the fossil record of monitor lizards. The similar lengths of the fore- and hindlimbs in this new taxon are unusual among the total group Varanidae and suggest it may have had a different lifestyle, at least from the contemporaneous North American S. ensidens. This article is part of the theme issue 'The impact of Chinese palaeontology on evolutionary research'.

A new mammal from the Lower Cretaceous Jehol Biota and implications for eutherian evolution.

Here we report on a new Early Cretaceous eutherian represented by a partial skeleton from the Jiufotang Formation at Sihedang site, Lingyuan City, Liaoning Province that fills a crucial gap between the earliest eutherians from the Yixian Formation and later Cretaceous eutherians. The new specimen reveals, to our knowledge for the first time in eutherians, that the Meckelian cartilage was ossified but reduced in size, confirming a complete detachment of the middle ear from the lower jaw. Seven hyoid elements, including paired stylohyals, epihyals and thyrohyals and the single basihyal are preserved. For the inner ear the ossified primary lamina, base of the secondary lamina, ossified cochlear ganglion and secondary crus commune are present and the cochlear canal is coiled through 360°. In addition, plesiomorphic features of the dentition include weak conules, lack of pre- and post-cingula and less expanded protocones on the upper molars and height differential between the trigonid and talonid, a large protoconid and a small paraconid on the lower molars. The new taxon displays an alternating pattern of tooth replacement with P3 being the last upper premolar to erupt similar to the basal eutherian Juramaia. Parsimony analysis places the new taxon with Montanalestes, Sinodelphys and Ambolestes as a sister group to other eutherians. This article is part of the theme issue 'The impact of Chinese palaeontology on evolutionary research'.

The origin of Rhinocerotoidea and phylogeny of Ceratomorpha (Mammalia, Perissodactyla).

Rhinoceroses have been considered to have originated from tapiroids in the middle Eocene; however, the transition remains controversial, and the first unequivocal rhinocerotoids appeared about 4 Ma later than the earliest tapiroids of the Early Eocene. Here we describe 5 genera and 6 new species of rhinoceroses recently discovered from the early Eocene to the early middle Eocene deposits of the Erlian Basin of Inner Mongolia, China. These new materials represent the earliest members of rhinocerotoids, forstercooperiids, and/or hyrachyids, and bridge the evolutionary gap between the early Eocene ceratomorphs and middle Eocene rhinocerotoids. The phylogenetic analyses using parsimony and Bayesian inference methods support their affinities with rhinocerotoids, and also illuminate the phylogenetic relationships and biogeography of Ceratomorpha, although some discrepancies are present between the two criteria. The nearly contemporary occurrence of various rhinocerotoids indicates that the divergence of different rhinocerotoid groups occurred no later than the late early Eocene, which is soon after the split between the rhinocerotoids and the tapiroids in the early early Eocene. However, the Bayesian tip-dating estimate suggests that the divergence of different ceratomorph groups occurred in the middle Paleocene.

Perissodactyl diversities and responses to climate changes as reflected by dental homogeneity during the Cenozoic in Asia.

Cenozoic mammal evolution and faunal turnover are considered to have been influenced and triggered by global climate change. Teeth of large terrestrial ungulates are reliable proxies to trace long-term climatic changes due to their morphological and physicochemical properties; however, the role of premolar molarization in ungulate evolution and related climatic change has rarely been investigated. Recently, three patterns of premolar molarization among perissodactyls have been recognized: endoprotocrista-derived hypocone (type I); paraconule-protocone separation (type II); and metaconule-derived pseudohypocone (type III). These three patterns of premolar molarization play an important role in perissodactyl diversity coupled with global climate change during the Cenozoic in Asia. Those groups with a relatively higher degree of premolar molarization, initiated by the formation of the hypocone, survived into Neogene, whereas those with a lesser degree of molarization, initiated by the deformation of existing ridges and cusps, went extinct by the end of the Oligocene. In addition, the hypothesis of the "Ulan Gochu Decline" is proposed here to designate the most conspicuous decrease of perissodactyl diversity that occurred in the latest middle Eocene rather than at the Eocene-Oligocene transition in Asia, as conventionally thought; this event was likely comparable to the contemporaneous post-Uintan decline of the North American land fauna.

A new early Eocene deperetellid tapiroid illuminates the origin of Deperetellidae and the pattern of premolar molarization in Perissodactyla.

Deperetellidae is a clade of peculiar, Asian endemic tapiroids from the early and middle Eocene. The previously published material mainly comprises maxillae, mandibles, and some postcranial elements. However, the absence of cranial materials and primitive representatives of the deperetellids obscures their phylogenetic relationships within Tapiroidea. Furthermore, derived deperetellids have completely molarized premolars, but the pattern of their evolution remains unclear. Here, we report a nearly complete skull and some carpals of a new basal deperetellid tapiroid, Irenolophus qii gen. et sp. nov., from the late early Eocene of the Erlian Basin, Inner Mongolia, China. We suggest that deperetellids (along with Tapiridae) probably also arose from some basal 'helaletids', based on the reduced, flat, lingually depressed metacones on the upper molars, the trend towards the bilophodonty on the lower molars, and a shallow narial notch with the premaxilla in contact with the nasal. The molarization of the premolars in Deperetellidae from Irenolophus through Teleolophus to Deperetella was initiated and gradually enhanced by the separation between the paraconule and the protocone. That pattern differs from the protocone-hypocone separation in helaletids, tapirids, and most rhinoceroses, and the metaconule-derived pseudohypocone in amynodontids. However, the specific relationship of deperetellids within Tapiroidea and the roles of different patterns of premolar molarization in perissodactyl evolution need further and comprehensive study.

Dexmedetomidine alleviates cerebral ischemia-reperfusion injury in rats via inhibition of hypoxia-inducible factor-1α.

Dexmedetomidine (Dex) was reported to reduce ischemia-reperfusion (I/R) injury in kidney and brain tissues. Thus, we aimed to study the role and mechanism of Dex in cerebral I/R injury by inhibiting hypoxia-inducible factor-1α (HIF-1α) and apoptosis. First, I/R injury models were established. Six groups were assigned after different treatments: sham, I/R, I/R+Dex, I/R+2-methoxyestradiol (2ME2) (HIF-1α inhibitor), I/R+CoCl 2 (HIF-1α activator), and I/R+Dex+CoCl 2 groups. Neurological function, cerebral infarction volume, survival, and apoptosis of brain cells were then analyzed. Besides, immunohistochemistry and Western blot analysis were used to detect the expression of HIF-1α, BCL-2[B-cell leukemia/lymphoma 2] adenovirus E1B interacting protein 3 (BNIP3), B-cell leukemia/lymphoma 2 (BCL2), BCL2[B-cell leukemia/lymphoma 2] associated X (Bax), and cleaved-caspase3 proteins in brain tissues. I/R rats showed cerebral infarction, increased neurological function score, number of terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL)-positive cells and HIF-1α-positive cells as well as decreased neurons. Inhibition of HIF-1α can reduce the apoptosis induced by I/R, and overexpression of HIF-1α can aggravate apoptosis in brain tissue of I/R rats. Furthermore, activation of HIF-1α expression blocks the inhibitory effect of Dex on neuronal apoptosis in I/R rats. Dex may inhibit the neuronal apoptosis of I/R rats by inhibiting the HIF-1α pathway and then improve the cerebral I/R injury in rats.

The divergence and dispersal of early perissodactyls as evidenced by early Eocene equids from Asia.

The earliest perissodactyls are represented by some basal equoid fossils from Euramerica near the Paleocene/Eocene boundary. Unequivocal early equoids have yet to be reported from the early Eocene of Asia, although other groups of early perissodactyls were indeed present in Asia. Here we report the earliest Eocene Asian equid, Erihippus tingae gen. et sp. nov., based on partial specimens initially assigned to the ceratomorph Orientolophus hengdongensis, from the Hengyang Basin of Hunan Province, China. The specimens previously assigned to 'Propachynolophus' hengyangensis from the same Lingcha fauna are split and now reassigned as an ancylopod Protomoropus? hengyangensis and a brontothere Danjiangia lambdodon sp. nov. The nearly simultaneous appearance of equids, ceratomorphs, ancylopods, and brontotheres in the Hengyang Basin suggests that the four main groups of perissodactyls diverged as early as, or no later than, the beginning of the Eocene (about 56 Ma), and displayed different dispersal scenarios during the early Eocene.

Fusion of detected multi-channel maternal electrocardiogram (ECG) R-wave peak locations.

BACKGROUND: Almost all promising non-invasive foetal ECG extraction methods involve accurately determining maternal ECG R-wave peaks. However, it is not easy to robustly detect accurate R-wave peaks of the maternal ECG component in an acquired abdominal ECG since it often has a low signal-to-noise ratio (SNR), sometimes containing a large foetal ECG component or other noises and interferences. This paper discusses, under the condition of acquiring multi-channel abdominal ECG signals, how to improve the robustness of maternal ECG R-wave peak detection. METHODS: On the basis of summarising the current single channel ECG R-wave peak detection methods, the paper proposed a specific fusion algorithm of detected multi-channel maternal ECG R-wave peak locations. The proposed entire algorithm was then tested using two databases; one database, created by us, was composed of 343 groups of 8-channel data collected from 78 pregnant women, and the other one, called the challenge database, was from the Physionet/Computing in Cardiology Challenge 2013, including 175 groups of 4-channel data. When using these databases, each group of data was classified into two parts, called the training part and the validation test part respectively; the training part was the first 8.192 s of each group of data and the validation test part was the next 8.192 s. RESULTS: To show the results, three evaluation parameters-sensitivity (Se), positive predictive value (PPV) and F1-are used. The validation test results for the database we collected are Se = 99.93 %, PPV = 99.98 %, and F1 = 99.95 %, while the results for the challenge database are Se = 99.91 %, PPV = 99.86 %, and F1 = 99.88 %. CONCLUSION: The results of the test show that the robustness of our proposed whole fusion algorithm was superior to that of other outstanding algorithms for maternal R-wave detection, and is much better than that of single channel maternal R-wave detection algorithms.

[Analytical Methods with Qualitative HPLC Fingerprint and Quantitative Measurement of Effective Components of Processed Asari Radix et Rhizoma].

OBJECTIVE: In order to provide the basis for quality standard and processing principle of processed Asari Radix et Rhizoma, an HPLC fingerprint of processed Asari Radix et Rhizoma was established and the contents of methyl eugenol and asarinin were determined. METHODS: The analytical column was Agligent Tc-C18 (250 mm x 4. 6 mm, 5 µm); A mixture of acetonitrile-0. 2% acetic acid solution was used as the mobile phase with gradient elution at the flow rate of 1. 0 mL/min. The wavelength was set at 285 nm and the column temperature was 30 °C. RESULTS: The fingerprint of processed Asari Radix et Rhizoma was established. The asarinin peak was taken as the reference peak. 22 common peaks were assigned, and two peaks were confirmed by comparing with the reference standards. The difference of components was not significant among the various processed products except ginger, honey and fried coke products, but the contents of effective constituents were different among the processed products. The retention rate of methyl eugenol in processed products was in a descending order as follows: wine > vinegar > liquorice > alkali-vinegar > fried coke > rice water system > honey > ginger > salt system > alkali. Methyl eugenol was increased 10% ~ 20% with wine processing and retained more than 95% with vinegar. The retention rate of asarinin in processed products was in declining as: rice water system > liquorice > alkali-vinegar > honey > salt system > wine > ginger > vinegar > alkali > fried coke. The processing techniques increased the content of asarinin except the alkali and fried coke products, and asarinin was increased more than 35% with rice water, alkali-vinegar or liquorice processing. CONCLUSION: The method is accurate and reliable, which can be used for the quality control of processed products of Asari Radix et Rhizoma.

[Study on pharmacokinetics-pharmacodynamics correlation of yin teng gu bi kang prescription].

OBJECTIVE: To study pharmacokinetics-pharmacodynamics (PK-PD) correlation of Yin Teng Gu Bi Kang (YTGBK) prescription through determination of Tanshinone II(A) concentration and the level of Malondialdehyde (MDA) in plasma in normal and blood stasis rats treated with YTGBK prescription. METHODS: The concentration of Tanshinone II(A) in the plasma was measured by HPLC-UV and loratadine was used as internal standard; Thiobarbituric acid reactive substance assay (TBARS) was adopted to determine the concentration of MDA in the plasma Area under the concentration-time curve (AUC) and area under the effect-time curve (AUE) were calculated using linear trapezoid rule. The correlation and regression analysis was performed by plotting AUE (Y) versus lgAUC (X) using linear regression. RESULTS: YTGBK prescription could significantly decrease MDA level in the plasma in above two different physiological rats at the analyzed time point (P < 0.05). Scatter plots of AUE-lgAUC showed an upward trend. The results of the correlation and regression analysis were as follows: Y = 53.367 X -30.780, r = 0. 822, P = 0.007 for normal rats and Y = 61.091 X -39.863, r = 0.777, P = 0.003 for model rats, respectively. CONCLUSION: There is a positive correlation between Tanshinone II(A) level in plasma and the antioxidant activity of YTGBK prescription in decreasing MDA level, which indicates that Tanshinone II(A) is the antioxidant effective substance of YTGBK prescription.

[Study on material basis of essential oil from Yin Teng Gu Bi Kang prescription on activating blood circulation].

OBJECTIVE: To explore the component difference of the serum containing essential oil from Yin Teng Gu Bi Kang prescription in pathologic and physiologic rat models, and to reveal the material basis of its efficacy of activating blood circulation. METHODS: The essential oils were obtained by CO2 supercritical fluid extraction and the ingredients of the essential oils in vitro and in vivo (under physiological and pathological status) were analyzed by GC-MS to compare differences of the essential oil under physiological and pathological status in rats. RESULTS: 32 components were identified with the main components of Z-ligustilide (39.23%) and d-limonene (21.7%) in the essential oil. In vivo analysis on the essential oil indicated that 16 components were identified, 7 existed originally in essential oil and 9 were metabolites under physiological status; while 22 components were identified, 10 existed originally in essential oil and 12 were metabolites under pathological status (acute blood stasis). There were 7 common prototypes and 8 common metabolites under different physiological status. CONCLUSION: The absorption and metabolism of essential oils were affected by blood stasis and the compounds migrating to blood may be the effective substance in activating blood circulation.

[Comparison of pharmaceutical chemistry difference of effective parts from yin teng gu bi kang prescription in normal rats and rats with acute blood stasis].

OBJECTIVE: To elucidate the material basis of Yin Teng Gu Bi Kang Prescription (YTGBKP) for efficacy of promoting blood circulation by means of comparing the pharmaceutical chemistry difference of effective parts in normal rats and rats with acute blood stasis. METHODS: The pharmaceutical chemistry fingerprints of effective parts under physiological and pathological status (acute blood stasis) were established by HPLC,and the in vitro and in vivo chromatographic peaks were compared and analyzed. RESULTS: Five batches of drug-containing plasma samples had 14 chromatographic peaks under normal physiological status,among which 3 rooted in plasma, 9 existed originally in YTGBKP,2 were metabolites. The compound with retention lime at 12 min was identified as ferulic acid by comparing with reference standard; While under pathological status (acute blood stasis), five batches of the drug-containing plasma samples had 14 chromatographic peaks, among which 3 rooted in plasma, 9 existed originally in YTGBKP, 2 were metabolites. The compounds with retention time at 12 min and 32 min were identified as ferulic acid and icariin respectively by comparing with reference standards. There were 10 common peaks under normal physiological and pathological status (acute bloodl stasis) excluding peaks in blank plasma. The intensity of the common peaks produced under pathological status was stronger than that under normal physiological status significantly; Variance analysis showed that there were significant differences (P < 0.05) in peak areas of 3 peaks. CONCLUSION: Blood stasis has influence on the absorption and metabolism of most ingredients from YTGBKPi; Prototypes and metabolites may be the effective substance on promoting blood circulation.

Inhibitory effect of organic carbon on CO2 fixing by non-photosynthetic microbial community isolated from the ocean.

The inhibitory effect of organic carbon on CO(2) fixation (CF) by the non-photosynthetic microbial community (NPMC) and its mechanism were studied. The results showed that different concentrations of glucose inhibited CF to some extent. However, when these microorganisms pre-cultured with glucose were re-cultured without organic carbon, their CF efficiency differed significantly from the control based on the glucose concentration in the pre-culture. ATP as bioenergy and NADH as reductant had no obvious inhibitory effect on CF; conversely, they improved CF efficiency to some extent, especially when both were present simultaneously. These results implied that not all organic materials inhibited CF by NPMC, and only those that acted as good carbon sources, such as glucose, inhibited CF. Moreover, some metabolites generated during the catabolism of glucose by heterotrophic metabolism of NPMC might inhibit CF, while other cumulated materials present in the cell interior, such as ATP and NADH, might improve CF.