Identifying the generator matrix of a stationary Markov chain using partially observable data.

Given that most states in real-world systems are inaccessible, it is critical to study the inverse problem of an irreversibly stationary Markov chain regarding how a generator matrix can be identified using minimal observations. The hitting-time distribution of an irreversibly stationary Markov chain is first generalized from a reversible case. The hitting-time distribution is then decoded via the taboo rate, and the results show remarkably that under mild conditions, the generator matrix of a reversible Markov chain or a specific case of irreversibly stationary ones can be identified by utilizing observations from all leaves and two adjacent states in each cycle. Several algorithms are proposed for calculating the generator matrix accurately, and numerical examples are presented to confirm their validity and efficiency. An application to neurophysiology is provided to demonstrate the applicability of such statistics to real-world data. This means that partially observable data can be used to identify the generator matrix of a stationary Markov chain.

Behavioral responses of cave-roosting bats to artificial light of different spectra and intensities: Implications for lighting management strategy.

Artificial light at night has become an emerging environmental pollutant, posing a serious threat to biodiversity. Cave-roosting animals are vulnerable to light pollution due to long-term adaptation to nocturnal niches, and the problem is especially severe in the context of cave tourism and limestone mining. Mitigating the adverse impacts of artificial light on cave-dwelling animals presents a challenge. This study aimed to assess the relative contributions of spectral parameters and light intensity to the emergence behavior of nine cave-roosting bat species: Rhinolophus macrotis, Rhinolophus pearsonii, Rhinolophus rex, Rhinolophus pusillus, Rhinolophus siamensis, Rhinolophus sinicus, Hipposideros armiger, Myotis davidii, and Miniopterus fuliginosus. We manipulated light spectra and intensities through light-emitting diode (LED) lighting and gel filters at the entrance of bat roost. We monitored nightly passes per species to quantify bat emergence under the dark control and ten lighting conditions (blue, green, yellow, red, and white light at high and low intensities) using ultrasonic recording. Our analyses showed that the number of bat passes tended to be reduced in the presence of white, green, and yellow light, independent of light intensity. In contrast, the number of bat passes showed no pronounced differences under the dark control, blue light, and red light. The number of bat passes was primarily affected by LED light's blue component, red component, peak wavelength, and half-width instead of light intensity. These results demonstrate that spectral parameters of LED light can significantly affect emergence behavior of cave-dwelling bats. Our findings highlight the importance of manipulating light colors to reduce the negative impacts of light pollution on cave-roosting bats as a function of their spectral sensitivity. We recommend the use of gel filters to manage existing artificial lighting systems at the entrance of bat-inhabited caves.

Artificial light affects foraging behavior of a synanthropic bat.

Artificial light at night has been considered an emerging threat to global biodiversity. However, the impacts of artificial light on foraging behavior in most wild animals remain largely unclear. Here, we aimed to assess whether artificial light affects foraging behavior in Asian parti-colored bats (Vespertilio sinensis). We manipulated the spectra of light-emitting diode (LED) lighting in a laboratory. Using video and audio recording, we monitored foraging onset, total foraging time, food consumption, freezing behavior (temporary cessation of body movement), and echolocation vocalizations in triads of bats under each lighting condition. Analyses showed that the foraging activities of experimental bats were reduced under LED light. Green, yellow, and red light had greater negative effects on bats' foraging onset, total foraging time, and food consumption than white and blue light. LED light of different spectra induced increased freezing time and echolocation vocalizations in captive bats, except for the white light. The peak wavelength of light emission correlated positively with freezing time, estimated echolocation pulse rate (the number of echolocation pulses per minute), and foraging onset, but negatively with total foraging time and food consumption. These results demonstrate that artificial light disturbs foraging behavior in Asian parti-colored bats. Our findings have implications for understanding the influencing mechanism of light pollution on bat foraging.

Airport noise disturbs foraging behavior of Japanese pipistrelle bats.

The expansion of anthropogenic noise poses an emerging threat to the survival and reproductive success of various organisms. Previous investigations have focused on the detrimental effects of anthropogenic noise on the foraging behavior in some terrestrial and aquatic animals. Nevertheless, the role of airport noise in impairing foraging activities of most wild animals has been neglected. Here, we aimed to assess whether foraging behavior in free-living Japanese pipistrelle bats (Pipistrellus abramus) can be disturbed by airport noise. We used audio recording to monitor foraging activities of bats at 11 sites around the runway of a municipal airport. We quantified noise level and spectra, aircraft activity, habitat type, nightly temperature, wind speed, and moon phase for each site. The analysis revealed that noise level and aircraft activity were significant negative predictors for the number of bat passes and feeding buzzes around the runway, even after controlling for the effects of other environmental factors. There was no marked spectral overlap between bat echolocation pulses and airport noise in the presence and absence of low-flying aircraft. The spectro-temporal parameters of echolocation vocalizations emitted by bats were dependent on noise level, aircraft activity, and habitat type. These results provide correlative evidence that airport noise can reduce foraging activities of wild pipistrelle bats. Our findings add to the current knowledge of adverse impacts of airport noise on foraging bats in artificial ecosystems and provide a basis for further research on the mechanisms behind noise pollution near airports.

Artificial light reduces foraging opportunities in wild least horseshoe bats.

Artificial light at night has been proposed as a global threat to biodiversity. Insectivorous bats are strictly nocturnal animals that are vulnerable to disruption from artificial light. Given that many light-sensitive bats tend to avoid night light during roost departure, it is often assumed that nighttime light pollution reduces their foraging opportunities, albeit empirical evidence in support of this hypothesis remains elusive. Here, we used least horseshoe bats, Rhinolophus pusillus, to assess whether white artificial light is detrimental for the opportunities of foraging. We manipulated the levels of ambient illumination and perceived predation risk inside the bat roost. We monitored bats' emergence activity using high-speed video and audio recording systems. DNA-based faecal dietary analysis and insect survey were applied to determine activity time of prey in foraging areas. Following experimentally manipulation of white light-emitting diode (LED) lighting 0-15 min after sunset, bat pass, flight duration, and echolocation pulse emission decreased. The mean emergence time of bats flying out was delayed by 14 min under lit treatment compared with the dark control. Only 10% of bats left for foraging during 40 min of light exposure. Aversive effects of LED light on bat emergence were robust regardless of the presence of a potential predator. Insect prey reached a peak of abundance between 30 and 60 min after sunset. These results demonstrate that white artificial light hinders evening emergence behavior in least horseshoe bats, leading to a mismatch between foraging onset and peak food availability. Our findings highlight that light pollution overrides foraging onset, suggesting the importance of improving artificial lighting scheme near the roosts of light-sensitive bats.

[Expression and its clinical significance of SLC22A18 in non-small cell lung cancer].

BACKGROUND AND OBJECTIVE: It has been proven that multidrug resistance (MDR) is the main cause of chemotherapy failure in lung cancer. Research on emergence mechanisms of MDR has great clinical significance in improving the curative efficiency of lung cancer chemotherapy. Proteins encoded by the SLC22A18 gene, which is similar to the transmembrane transporter, may influence the sensitivity of chemotherapeutics as well as the metabolism and growth of cells. In addition, these proteins probably have some effect on the development of lung cancer MDR. The aim of the present study is to investigate the expression of SLC22A18 protein in non-small cell lung cancer (NSCLC) as well as in corresponding normal lung tissue. Furthermore, the relationship between SLC22A18 expression and pathological grade and TNM stage is analyzed. METHODS: The expression of SLC22A18 was detected by EnVinsion in 96 cases with NSCLC and in corresponding normal lung tissue. Statistical analysis was performed using SPSS 17.0 statistical software. RESULTS: SLC22A18 was mainly located in cell membrane and cytoplasm. The expression level of SLC22A18 in NSCLC was significantly higher than that in normal tissue (P<0.01). The positive rates in squamous cell lung cancer and lung adenocarcinoma were 68% and 78.2%, respectively (P<0.05). Moreover, the higher expression of SLC22A18 was associated with lower histological grade and later TNM stage (P<0.05). CONCLUSION: SLC22A18 protein is overexpressed in NSCLC, and its expression is correlated with pathological grade and TNM stage. These findings provide the experimental basis for investigating the role of tumor and chemoresistance.

[Experimental study on acute respiratory distress syndrome and analysis of relevant factors in rabbits subjected to thoracic blast trauma].

OBJECTIVE: To reproduce acute respiratory distress syndrome (ARDS) model in rabbit induced by chest blast injury and to analyze the pathogenesis and causes of early death in order to provide the basis for the early diagnosis of lung blast injury and its early warning system to facilitate an early treatment. METHODS: Sixty healthy New Zealand white rabbits were divided into six groups according to the different explosion distance with the random number table method. The survival rate and its resulting pathological changes were observed and patho physiological indexes and lung fluid content were determined at sequential time points post explosion. RESULTS: Shock wave pressure less than 1 210.5 mm Hg (1 mm Hg=0.133 kPa, group A, B) resulted in limited injury to the lung within grade 2 as assessed with the abbreviated injury scale (AIS). The rabbits in these groups recovered soon and survived without any complication. Shock pressure higher than 2 036.1 mm Hg (group D, E) caused severe injuries to the lung, including deep laceration , disruption of lung hilus and large hematoma in the lung, and the injury severity of lungs was assessed above grade 5 as assessed with AIS. All rabbits died within 1 hour post explosion. The groups described above failed to meet the demand of an ARDS model for the present study. Shock wave pressure at 1 917.3 mm Hg (group C) produced extensive contusion from grade 4 to grade 5 as assessed with AIS. The rabbits survived in poor general condition, and arterial partial pressure of oxygen (PaO(2)) lowered within 6 hours . Pathological examination showed extensive and constant multi focal bleeding involving more than four lobes. The alveolar wall was edematous, with partial rupture and alveolar fusion in lung tissues was observed in the group C. Alveoli were filled with inflammatory cells, and hyaline membrane was formed occasionally . Compared with control group, the wet to dry weight ratio (W/D) in lungs increased obviously (6.46±0.24 vs. 3.98±0.19, P<0.01) in group C within 6 hours postinjury. The contents of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) in plasma and bronchoalveolar lavage fluid (BALF) were also increased distinctly compared with the control group [TNF-α (ng/L) in plasma: 328.89±6.26 vs. 62.12±2.98, TNF-α (ng/L) in BALF: 164.87±4.59 vs. 29.51±1.12; IL-6 (ng/L) in plasma: 128.51±4.13 vs. 19.32±1.53, IL-6 (ng/L) in BALF: 94.97±1.14 vs. 22.72±0.19, all P<0.05]. CONCLUSION: In an airtight environment, rabbit ARDS model can be reproduced successfully by blast injury with 1 917.3 mm Hg explosion pressure; TNF-α and IL-6 are involved in the pathogenesis and development of ARDS in blast injury. Pneumothorax as a result of lung rupture is the chief reason for early death and dysfunction of circulatory system is also an important reason in producing early death.

[Expression and Clinical Significance of ABCC10 in the Patients with Non-small Cell Lung Cancer.].

BACKGROUND: Multidrug resistance (MDR) is the main reason of the failure of chemotherapy in lung cancer. The MDR mechanism in lung cancer is complex, which relates to sorts of drug resistant genes. ABCC10 is a recently identified member of a subset of the C family of ATP-binding cassette (ABC) transporters. The drug resistance capability of ABCC10 has been partly determined. The aim of the study is to investigate the expression of ABCC10 in non small cell lung cancer (NSCLC) and normal tissues, and analyze the relationship between ABCC10 expression level and clinical features, such as TNM stages, histological types and pathological grades. METHODS: The expression of ABCC10 was detected in squamous cell carcinoma, adenocarcinoma and normal lung tissues by immunohistochemistry. Then the statistical analysis was performed. RESULTS: The expression of ABCC10 was mainly located in cell membrane and cytoplasm. There were significant differences between the expression of ABCC10 in NSCLC and normal tissues (P<0.01). The positive rates in squamous cell carcinoma and adenocarcinoma were 73.26% and 81.16%, respectively with significant differences (P<0.05). There were significant differences among histological grades in squamous cell carcinoma (P<0.01). There were significant differences among histological grades and TNM stages respectively in adenocarcinoma (P<0.01). CONCLUSIONS: ABCC10 is overexpressed in NSCLC. The expression of ABCC10 in adenocarcinoma is higher than that in squamous cell carcinoma. The expression in adenocarcinoma is correlated to pathological grades and TNM stages. The results of this study would be benefit for further study of ABCC10 in tumor and its chemoresistance.

[Expression and its Clinical Significance of NOK, EGFR in NSCLC.].

BACKGROUND: NOK (Novel Oncogene with Kinase-domain) is a newly identified receptor protein-tyrosine kinases (RPTKs) subfamily, which possesses strong oncogenic potential including enhancing cell transformation, tumorigenesis, invasion and metastasis. However, NOK protein lacks extracellular domain, and how the NOK is activated by the membrane receptor and the expression of NOK in non small cell lung cancer (NSCLC) are not clear. Our aim of this study was to investigate the expressions of NOK, EGFR proteins in NSCLC. METHODS: The expression rates of NOK, EGFR proteins in 155 cases with NSCLC was deteced by immunohistochemical stain; The clinical correlations between two proteins were analyzed by statistics. RESULTS: The NOK positive expression was mainly located in cytoplasm and EGFR was mainly located in the plasma membrane and cytoplasm. NOK, EGFR proteins were high expressed in NSCLC and there were extremely differences comparing the expression of NOK, EGFR proteins in squamous cell lung cancer, lung adenocarcinoma with those in corresponding normal tissue respectively (P<0.001); and there were no significant differences between the two kinds of the cancers for their comparison of NOK, EGFR expression (P=0.099; P=0.23); however, there were significant differences for NOK and EGFR expression among histological grades and TNM stages in squamous cell lung cancers, lung adenocarcinoma (P<0.01). There were correlation between positive and intensity of NOK and EGFR expression in whatever total NSCLC or squamous cell lung cancer or lung adenocarcinoma (P<0.001), while the correlation coefficients(rs) were 0742, 0.722, 0.756 respectively. CONCLUSIONS: The NOK proteins are highly expressed in the NSCLC, and the expression rates of NOK proteins are correlated with the cancers' histological grades and TNM stages, which may be concern with tumorgenesis and progression; the positive expression rate and intensity of NOK protein correlate well with the expression of EGFR protein in NSCLC, which the activation of NOK probably owe to EGFR activation, all that would provide evidence for further study on the effective mechanism of NOK in the tumorigenesis or tumor progression.

Dynamics of moment neuronal networks.

A theoretical framework is developed for moment neuronal networks (MNNs). Within this framework, the behavior of the system of spiking neurons is specified in terms of the first- and second-order statistics of their interspike intervals, i.e., the mean, the variance, and the cross correlations of spike activity. Since neurons emit and receive spike trains which can be described by renewal--but generally non-Poisson--processes, we first derive a suitable diffusion-type approximation of such processes. Two approximation schemes are introduced: the usual approximation scheme (UAS) and the Ornstein-Uhlenbeck scheme. It is found that both schemes approximate well the input-output characteristics of spiking models such as the IF and the Hodgkin-Huxley models. The MNN framework is then developed according to the UAS scheme, and its predictions are tested on a few examples.