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Cooking fumes (CFs) are mixtures of many toxic components, such as aldehydes, heterocyclic amines, polycyclic aromatic hydrocarbons, fat aerosols and particulate matters. CFs exposure has been proven to be associated with many diseases. Lung cancer takes the leading place among the diseases being reported caused by CFs exposure. Molecular and biochemical studies have found that CFs exposure may lead to lung cancer by gene damage, formation of reactive oxygen species, blockage of related proteins' function, and even cell death. However, reviews about the mechanisms of how CFs exposure leads to lung cancer are still lacking. Elucidation of the mechanisms of lung cancer caused by CFs exposure may provide a new insight into the prevention of lung cancer caused by CFs exposure, as well as laying the foundation for the toxicity study of CFs. In this minor review, the mechanisms of how CFs exposure leads to lung cancer were summarized and discussed.

Pinus thunbergii is one of the main tree species of the coastal forest in Shandong peninsula,China,and plays important roles in resisting natural perturbation and maintaining its ecological functions.Adapted to the sandy ocean coast habitats and the windy conditions,the species has developed shrubby crown due to compensatory response,an important mechanism to adapt the stress environments,induced by the insect boring wounds through still unknown mechanisms.For the purpose of sustainable management of P.thunbergii forests,this study elucidated the mechanism of compensatory response and its role in the formation process of crown architecture by comparing growth characteristics of the pre-and post-boring treatments.We randomly sampled 20 trees from the coastal pine forests for monitoring the morphological changes of buds and the crown dimension during March 2009 and May 2010,and identified the shoots into three age categories according to the morphological responses to the stressing perturbation.The results showed that 1) the current and next year shoots clearly increased by 1.56 and 1.4 times after the boring,while the treatment effect on the current shoots was higher than that of the next year.It indicated that the compensatory response was persistent but gradually decreased.The compensatory response of leaf module showed similar trend but was statistically insignificant among shoots of different ages.2) A close relationship between the compensatory growth and the position of one year shoots was found,and the branch length and leaf module near the top was increased 1.75 and 1.43 times in average,respectively,after the boring,but the compensatory growth near the bottom was not tested significant.3) The process of adapted architecture begun with the change of bud module quantity and forms.The mortality of bud increased by 5.4 times which could be explained by density effect,and the number of vegetative bud increase after boring.The production of vegetative bud increased by 1.55 times on average,but the production of generative bud had no significant difference.These results suggested that the boring induced compensatory response stimulates invest in vegetative growth.4) The shoot leaders stopped growing after the boring and the number of bifurcation was increased resulting in a 25% improvement in the box-counting dimension(Db) of shoot.There was a post-peak functional relationship between the crown dimension and damage rate of shoot: the crown dimension reached the maximum while the damage rate was also increased to about 70%.This compensatory response might enhance the competitive ability of the species for space.5) The total shoot and leaf biomass did not have significant differences between pre-and post treatment indicating an equal-compensatory growth.This study revealed that apical dominance removal and the consequent compensatory responses to the boring wounds resulted in some drastic changes in crown architecture of Pinus thunbergii in the stressed coastal environments.The morphological changes of bud and their deviating normal development,as well as the crown dimension could be used as the indicators of this compensatory growth.Further studies should focus on the physiological mechanisms of the stress responses of the species.

To improve the efficiency and accuracy of calibration in frequency domain for a distributed electromagnetic receiver,a calibration method based on multi-frequency pseudo-random signal was proposed and the generation and detection of the signals were investigated.According to the analytical expression of multi-frequency pseudo-random signals,the amplitude and distribution characteristics of the main frequency were analyzed,and a high-precision bipolar calibration source was produced through a Field Programming Gate Array(FPGA) to achieve the encoding synthesis of pseudo-random signals.Based on the noise suppression principle of correlation detection,an iterative method with multiple times for the amplitude and phase of a noisy multi-frequency calibration output signal was given,then it was validated by a simulation.Finally,the acquisition channels of the distributed dual-channel electromagnetic receiving system and a magnetic field sensor were calibrated actually.The results indicate that the amplitude error and the phase error are less than 2% and 1°,respectively,while the outside noise is not greater than the calibration output signal.The calibration method is fast,accurate and can be used in the frequency-domain calibration of distributed electromagnetic receiving systems in various field environments.

To solve the problem of inaccurate peak demodulation resulted from the system uncertain phase shift in Amplitude Modulation(AM) for a capacitive displacement sensor,an AM capacitive displacement sensor based on an improved delayed feedback peak detector circuit was proposed and its applied functional blocks and circuits were investigated.Firstly,the measurement principles of the AM capacitive displacement sensor and its detection circuit were analyzed.Based on generation principle of phase shift with the AM signal,an improved delayed feedback peak detector was presented against the problem of inaccurate peak demodulation.Then,the AM capacitive displacement sensor was prototyped using printed circuit boards and its performance indicators were tested as well.Finally,experimental results and errors were discussed.It indicates that the linearity of the delayed feedback peak detector circuit is better than 0.05%,the data shift of prototyped sensor is less than 10 nm/30 min,and the maximum deviation of sensor is 36 nm within the measuring range of 0~25 μm.It concludes that the delayed feedback peak detector circuit can effectively solve the problem of inaccurate peak detector resulted from the system uncertain phase shift,and the proposed AM capacitive sensor can satisfy the requirements of high precision measurement.

When the large-scale aerial photography is implemented,it is often need to obtain bigger coverage width to improve efficiency by single flight course fly.But,the coverage width of single aerial camera is limited,for realizing the coverage width specification of not less than 5.2H(H is defined as photograph height),based on some actual project,a method that the coverage width is improved by utilizing camera integration with short focal length is proposed.In this paper,some algorithms of twin-camera,tri-camera and four-camera for improving the coverage length are discussed.Furthermore,an optimum scheme is chosen by calculating the forward image motion velocity difference.This method has been widely used in the field of surveillance of naturaldisaster and re-establishment survey.Besides,the method is also feasible for scanning-aerial camera,short focal length plane array CCD camera and film camera.

A heterodyne detection experiment is established to measure the constant rotation velocity and the variable velocity of targets,in which the diffuse reflectance target and simple harmonic motion model are taken as research targets.For uniform rotation velocity measurement,the heterodyne method and amplitude modulation velocity measurement are conducted at the same time to measure the rotation velocity of a diffusion target in two directions and 133 sets of results are obtained.Moreover,the variable velocity is measured for a target with like-harmonic motion by the same optical system,and the spectrum video is processed by the Matlab software to get the velocity.Tested results show that,in the uniform rotation velocity range from 0.05 to 16 m/s,the average relative error for positive and negative rotation analytical measurements are only 0.51% and 0.42%,respectively.In a variable velocity measurement for positive and negative rotations,the maximum speed are 0.555 6 and-0.659 m/s,respectively.The results indicate that the measurement has a higher accuracy and a higher Signal to Noise Ratio(SNR) for a clear mid-frequency spectrum can be seen.

A new method of achieving steel band tension by using cylinder helix torsional spring was presented in the course of studying the gapless linear transmission system.The principle of the gapless linear transmission system was briefly described in this paper.The characteristics of the cylinder helix torsional spring were researched.The change of the steel band's tension and elastic deformation,as well as the encoder's output error was analyzed because of the cylinder helix torsional spring's inflection in periodic motion.A mathematical model was established and tested.The results indicated that the cylinder helix torsional spring could better achieve the function.It is concluded that the method can meet the design requirements。