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This paper is concerned with the detection of “features” of visual patterns, in particular with a view to the construction of a reading automaton. The features can be divided into micro‐features and macro‐features. It is much more difficult to detect a macro‐feature than a micro‐feature of a pattern. For the detection of at least a large class of macro‐features interative processes seem to be the most appropriate, since by these processes the detection of a macro‐feature is reduced to the repeated detection of a micro‐feature, while further a given micro‐feature can be displaced, by such a process, over virtually the whole screen on which the image is projected. Two examples of such processes are discussed.

Although first rank symptoms focus on positive symptoms of psychosis they are shared by a number of psychiatric conditions. The difficulty in differentiating bipolar disorder from schizophrenia with affective features has led to a third category of patients often loosely labeled as schizoaffective. Research in schizophrenia has attempted to render the presence or absence of negative symptoms and their relation to etiology and prognosis more explicit. A dichotomous population is a recurring theme in experimental paradigms. Thus, schizophrenia is defined as process or reactive, deficit or non-deficit and by the presence or absence of affective symptoms. Laboratory tests confirm the clinical impression showing conflicting responses to dexamethasone suppression and clearly defined differences in autonomic responsiveness, but their patho-physiological significance eludes mainstream theory. Added to this is the difficulty in agreeing to what exactly constitutes useful clinical features differentiating, for example, negative symptoms of a true deficit syndrome from features of depression. Two recent papers proposed that the general and specific cognitive features of schizophrenia and major depression result from a monoamine-cholinergic imbalance, the former due to a relative muscarinic receptor hypofunction and the latter, in contrast, to a muscarinic hypersensitivity exacerbated by monoamine depletion. Further development of these ideas will provide pharmacological principles for what is currently an incomplete and largely, descriptive nosology of psychosis. It will propose a dimensional view of affective and negative symptoms based on relative muscarinic integrity and is supported by several exciting intracellular signaling and gene expression studies. Bipolar disorder manifests both muscarinic and dopaminergic hypersensitivity. The greater the imbalance between these two receptor signaling systems, the more the clinical picture will resemble schizophrenia with bizarre, incongruent delusions and increasingly disorganized thought. The capacity for affective expression, by definition a non-deficit syndrome, will remain contingent on the degree of preservation of muscarinic signaling, which itself may be unstable and vary between trait and state examinations. At the extreme end of muscarinic impairment, a deficit schizophrenia subpopulation is proposed with a primary and fixed muscarinic receptor hypofunction.

The genomic profile of bipolar disorder and schizophrenia overlap and both have a common dopaminergic intracellular signaling which is hypersensitive to various stressors. It is proposed that the concomitant muscarinic receptor upregulation differentiates the syndromes, being marked in bipolar disorder and rather less so in schizophrenia. From a behavioral point of view non-deficit syndromes and bipolar disorder appear most proximate and could be reclassified as a spectrum of affective psychosis or schizoaffective disorders. Because of a profound malfunction of the muscarinic receptor, the deficit subgroup cannot express a comparable stress response. None -theless, a convergent principle of psychotic features across psychiatric disorders is a relative monoaminergic-muscarinic imbalance in signal transduction.

Smart biosensors that can perform sensitive and selective monitoring of target analytes are tremendously valuable for trinitrotoluene (TNT) explosive detection. In this research, the pre-developed sensor was integrated with biological receptors in which they enhanced the sensitivity of the sensor. This is due to conjugated polydiacetylene onto a peptide-based molecular recognition element (Trp-His-Trp) for TNT molecules in graphene field-effect transistors (GR-FETs) as biosensor that is capable of responding to the presence of a TNT target with a colorimetric response. The authors confirmed the efficacy of the receptor while being attached to polydiacetylene (PDA) by observing the binding ability between the Trp-His-Trp and TNT to alter the electronic band structure of the PDA conjugated backbones. The purpose of this paper is to demonstrate a modular system capable of transducing small-molecule TNT binding into a detectable signal. The details of the real-time and selective TNT biosensor have been reported.

Following an introduction, this paper describes the way of fabrication GR-FETs with conventional photolithography techniques and the other processes, which is functionalized by the TNT peptide receptors. The authors first determined the essential TNT recognition elements from UV-visible spectrophotometry spectroscopy for PDA sensor unit fabrication. In particular, the blue percentage and the chromic response were used to characterize the polymerization parameter of the conjugated p backbone. A continuous-flow trace vapor source of nitroaromatics (two, four, six-TNT) was designed and evaluated in terms of temperature dependence. The TNT concentration was measured by liquid/gas extraction in acetonitrile using bubbling sequence. The sensor test is performed using a four-point probe and semiconductor analyzer. Finally, brief conclusions are drawn.

Because of their unique optical and stimuli-response properties, the polydiacetylene and peptide-based platforms have been explored as an alternative to complex mechanical and electrical sensing systems. Therefore, the authors have used GR-FETs with biological receptor-PDAs as a biosensor for achieving high sensitivity and selectivity that can detect explosive substances such as TNT. The transport property changed compared to that of the field-effect transistors made by intrinsic graphene, that is, the Dirac point position moved from positive Vg to negative Vg, indicating the transition of graphene from p-type to n-type after annealing in TNT, and when the device was tested from RT, the response of the device was found to increase linearly with increasing concentrations. Average shifting rate of the Dirac peak was obtained as 0.1-0.3 V/ppm. The resulting sensors exhibited at the limit ppm sensitivity toward TNT in real-time, with excellent selectivity over various similar aromatic compounds. The biological receptor coating may be useful for the development of sensitive and selective micro and nanoelectronic sensor devices for various other target analytes.

The detection of illegally transported explosives has become important as the global rise in terrorism subsequent to the events of September 11, 2001, and is at the forefront of current analytical problems. It is essential that a detection method has the selectivity to distinguish among compounds in a mixture of explosives. So, the authors are reporting a potential solution with the designing and manufacturing of electrochemical biosensor using polydiacetylene conjugated with peptide receptors coated on GR-FETs with the colorimetric response for real-time detection of TNT explosives specifically.

Early detection of forest fires offers the chance to put the fire out before it gets out of control. The purpose of this paper is to look into nature and to learn how certain insects detect remote forest fires. A small group of highly specialized insects that have been called pyrophilous is attracted by forest fires and approaches fires sometimes from distances of many kilometers. As a unique feature some of these insects are equipped with infrared (IR) receptors, which in case of two species of jewel beetles (family Buprestidae) are used for fire detection.

The paper has investigated the IR receptors of the pyrophilous beetles with various morphological techniques including scanning electron microscopy, transmission electron microscopy, neuroanatomy and the paper also investigated the thermo-/mechanical properties of the IR receptors by nanoindentation. Data were used for subsequent modeling of a biomimetic technical sensor. Finally, a macroscopic prototype was built and tested.

This biological principle was transferred into a new kind of uncooled technical IR receptor. A simple model for this biological IR sensor is a modified Golay sensor in which the gas has been replaced by a liquid. Here, the absorbed IR radiation results in a pressure increase of the liquid and the deflection of a thin membrane. For the evaluation of this model, analytical formulas are presented, which permits the calculation of the pressure increase in the cavity, the deformation of the membrane and the time constant of an artificial leak to compensate ambient temperature changes. Some organic liquids with high thermal expansion coefficients may improve the deflection of the membrane compared to water.

Results so far obtained suggest that it seems promising to take the photomechanic IR receptors of pyrophilous jewel beetles as models for the building of new uncooled IR sensors. The beetle receptors have been shaped by evolution since thousands of years and, therefore, can be considered as highly optimized sources of inspiration for new technical sensors suitable for remote fire detection.

The purpose of this paper is to investigate the correlation and mechanism between international students and inbound tourism.

Taking 269 prefecture-level cities in China as a sample, bringing international students and inbound tourism into the same analytical framework, the paper applies the fixed-effects model, instrumental variables model and mediating effects model to investigate the impact of international students on inbound tourism.

International students significantly contribute to the increase in inbound tourists and tourism revenue in China, which remain valid after a series of robustness tests. When the relocation data of Chinese urban universities and faculties in the 1950s are used as an instrumental variable for the potential endogenous problems of international students, the results are still valid. Heterogeneity research shows that the impact of international students on inbound tourism has heterogeneous effects in different regions. In addition, the mechanism analysis shows that international students promote China’s inbound tourism mainly through two channels: the economic growth effect and the human capital effect.

This paper provides evidence of the correlation between international students and inbound tourism in developing countries. However, as the data for the study are all from China, caution should be taken when applying the findings of this paper to other regions.

This paper provides evidence on the causal relationship between international students and inbound tourism in developing countries. However, as the data for the study are all from China, caution should be taken when applying the findings of this paper to other regions.

This paper creatively finds out the instrumental variables of international students with academic education to deal with the potential endogenous problems, and then identifies the causal relationship between international students and inbound tourism.

This paper creatively finds out the instrumental variables of international students to deal with the potential endogenous problems and then identifies the correlation between international students and inbound tourism.

本文将研究样本扩大到中国266个地级市, 将留学生和入境旅游纳入同一分析框架, 从游客规模和旅游收入两个方面衡量入境旅游规模, 并调查留学生对入境旅游规模的影响及其机制。

本文通过使用面板数据的固定效应模型、工具变量和的中介效应, 考察国际学生与入境旅游之间的因果关系。

留学生显著促进了中国入境旅游收入和游客数量的增长, 经过一系列稳健测试后, 上述结果仍然成立; 以20世纪50年代中国城市高校和院系的搬迁数据作为国际学生应对潜在内生性问题的工具变量, 结果仍然有效; 异质性研究表明, 留学生入境旅游效应在不同的时间和地区具有异质性; 在机制分析中, 留学生促进中国入境旅游主要通过三个渠道：经济增长效应、人力资本效应和外商投资效应。

本文为发展中国家提供了国际学生与入境旅游之间因果关系的证据。但由于研究数据均来自中国, 将本文的研究结果应用于其他地区时需谨慎。

本文为发展中国家提供了国际学生与入境旅游之间因果关系的证据。但由于研究数据均来自中国, 将本文的研究结果应用于其他地区时需谨慎。

本文创造性地找出留学生学历教育的工具变量以应对潜在的内生性问题, 进而识别留学生与入境旅游之间的因果关系。

本文创造性地找出留学生学历教育的工具变量以应对潜在的内生性问题, 进而识别留学生与入境旅游之间的因果关系。

Tomando como muestra 266 ciudades de China a nivel de prefectura, e integrando a los estudiantes internacionales y el turismo receptor en el mismo marco analítico, el documento aplica el modelo de efectos fijos, el modelo de variables instrumentales y el modelo de efectos mediadores para investigar el impacto de los estudiantes internacionales en el turismo receptor.

El propósito de este documento es investigar la relación causal y el mecanismo entre los estudiantes internacionales y el turismo receptor.

Los estudiantes internacionales contribuyen significativamente al aumento de los turistas entrantes y de los ingresos por turismo en China, que siguen siendo válidos tras una serie de pruebas de solidez. Cuando utilizamos los datos de reubicación de las universidades y facultades urbanas chinas en la década de 1950 como variable instrumental para los posibles problemas endógenos de los estudiantes internacionales, los resultados siguen siendo válidos. La investigación de la heterogeneidad muestra que el impacto de los estudiantes internacionales en el turismo receptor tiene efectos heterogéneos en las distintas regiones. Además, el análisis del mecanismo muestra que los estudiantes internacionales promueven el turismo receptor de China principalmente a través de tres canales: el efecto del crecimiento económico, el efecto del capital humano y el efecto de la inversión extranjera.

Este trabajo aporta pruebas sobre la relación causal entre los estudiantes internacionales y el turismo receptor en los países en desarrollo. Sin embargo, como todos los datos del estudio proceden de China, hay que ser prudentes a la hora de aplicar los resultados de este trabajo a otras regiones.

Este documento aporta pruebas sobre la relación causal entre los estudiantes internacionales y el turismo receptor en los países en desarrollo. Sin embargo, dado que todos los datos del estudio proceden de China, debe tenerse precaución a la hora de aplicar los resultados de este documento a otras regiones.

Este trabajo descubre de forma creativa las variables instrumentales de los estudiantes internacionales con formación académica para hacer frente a los posibles problemas endógenos y, a continuación, identifica la relación causal entre los estudiantes internacionales y el turismo receptor.

Este trabajo descubre de forma creativa las variables instrumentales de los estudiantes internacionales para tratar los posibles problemas endógenos, y luego identifica la relación causal entre los estudiantes internacionales y el turismo receptor.

This paper aims to provide a detailed review of weak interaction biosensors and several common biosensor methods for magnifying signals, as well as judiciously guide readers through selecting an appropriate detecting system and signal amplification method according to their research and application purpose.

This paper classifies the weak interactions between biomolecules, summarizes the common signal amplification methods used in biosensor design and compares the performance of different kinds of biosensors. It highlights a potential electrochemical signal amplification method: the G protein signaling cascade amplification system.

Developed biosensors which, based on various principles, have their own strengths and weaknesses have met the basic detection requirements for weak interaction between biomolecules: the selectivity, sensitivity and detection limit of biosensors have been consistently improving with the use of new signal amplification methods. However, most of the weak interaction biosensors stop at the research stage; there are only a minority realization of final commercial application.

This paper evaluates the status of research and application of weak interaction biosensors systematically. The G protein signaling cascade amplification system proposal offers a new avenue for the research and development of electrochemical biosensors.

Smart sensors based on graphene field effect transistor (GFET) and biological receptors are regarded as a promising nanomaterial that could be the basis for future generation of low-power, faster, selective real-time monitoring of target analytes and smaller electronics. So, the purpose of this paper is to provide details of sensors based on selective nanocoatings by combining trinitrotoluene (TNT) receptors (Trp-His-Trp) bound to conjugated polydiacetylene polymers on a graphene channel in GFET for detecting explosives TNT.

Following an introduction, this paper describes the way of manufacturing of the GFET sensor by using investigation methods for transferring graphene sheet from Cu foil to target substrates, which is functionalized by the TNT peptide receptors, to offer a system which has the capability of answering the presence of related target molecules (TNT). Finally, brief conclusions are drawn.

In a word, shortly after graphene discovery, it has been explored with a variety of methods gradually. Because of its exceptional electrical properties (e.g. extremely high carrier mobility and capacity), electrochemical properties such as high electron transfer rate and structural properties, graphene has already showed great potential and success in chemical and biological sensing fields. Therefore, the authors used a biological receptor with a field effect transistor (FET) based on graphene to fabricate sensor for achieving high sensitivity and selectivity that can detect explosive substances such as TNT. The transport property changed compared to that of the FET made by intrinsic graphene, that is, the Dirac point position moved from positive Vg to negative Vg, indicating the transition of graphene from p-type to n-type after annealing in TNT, and the results show the bipolar property change of GFET with the TNT concentration and the possibility to develop a robust, easy-to-use and low-cost TNT detection method for performing a sensitive, reliable and semi-quantitative detection in a wide detection range.

In this timeframe of history, TNT is a common explosive used in both military and industrial settings. Its convenient handling properties and explosive strength make it a common choice in military operations and bioterrorism. TNT and other conventional explosives are the mainstays of terrorist bombs and the anti-personnel mines that kill or injure more than 15,000 people annually in war-torn countries. In large, open-air environments, such as airports, train stations and minefields, concentrations of these explosives can be vanishingly small – a few parts of TNT, for instance, per trillion parts of air. That can make it impossible for conventional bomb and mine detectors to detect the explosives and save lives. So, in this paper, the authors report a potential solution with design and manufacture of a GFET sensor based on a biological receptor for real-time detection of TNT explosives specifically.