Notes from the field: wildlife rabies on an island free from canine rabies for 52 years--Taiwan, 2013.

Dog-to-dog transmission of rabies in Taiwan was eliminated in 1961; the island was considered canine rabies-free for 52 years. On July 16, 2013, three ferret-badgers (Melogale moschata) tested positive for rabies by fluorescent antibody testing at the Animal Health Research Institute, Council of Agriculture of Taiwan. This was the first time wild animals other than bats were tested. During 1999-2012, a total of 6,841 clinically healthy dogs and five apparently normal cats from shelters were tested and found negative for rabies. During 2009-2012, a total of 322 bats were tested and found negative for rabies.

Nanoscale measurements of conducting domains and current-voltage characteristics of chemically deposited polyaniline films.

Spatial variations in electric conductivity and evolutions of band structures of polyaniline (PANI) films have been studied by use of a so-called current-sensing atomic force microscope (CS-AFM) or atomic force microscope current image tunneling spectroscopy (AFM-CITS). PANI films were deposited chemically onto indium-tin oxide- (ITO-) glass substrates, and their thickness and doping levels were controlled by polymerization and acid-doping conditions. The conducting uniformity of the PANI films depends on their doping level and thickness. Conducting domains were observed in fully doped PANI film, even when the bias voltage was reduced to as small as 30 mV. High current flowing regions gradually disappeared when conducting PANI films were partially dedoped. The point-contact current-voltage (I-V) characteristics of conducting tip-polymer/ITO systems were investigated on PANI films with different thickness and degree of doping. Various types of I-V curves representing metallic, semiconducting, and insulating states were obtained depending on the aggregation of polymer chains and doping level of the polymer film. The band gap energies (estimated from the I-V or dI/dV-V curves) of emeraldine base (EB) (undoped polyaniline) films are all higher than 3.8 eV, and a wide distribution of the band gap energies (0-1.1 eV and 0.75-1.8 eV for fully and partially doped PANI thin films, respectively) was found in a single polymer film.

Effects of polymerization media on the nanoscale conductivity and current-voltage characteristics of chemically synthesized polyaniline films.

A current sensing atomic force microscope (CS-AFM) was used to probe the conducting homogeneity and band structures of fully doped polyaniline (PANI) films prepared from in situ chemical polymerization/deposition of aniline on indium tin oxide in various inorganic acids. The charge transport properties of PANI films depend on the film thickness as well as polymerization medium. Fluctuations in conductivity are observed on all acid-doped PANI films and the conducting homogeneity was dependent on the film thickness: the conductivity of thick film is more uniform. The current-voltage (I-V) characteristics of all thick (>200 nm) films displayed a metal-like behavior and conductivity as high as 40 S/cm was detected in high conducting regions of film thicker than 400 nm. Whereas thin (<120 nm) films revealed insulating, semiconducting, and semimetal conducting, wide distribution in conductivity and interband distances (estimated from the I-V ordI/dV-V curves) was found. The interband distances is 0-1.35, 0-1.0, and 0-0.78 eV for thin PANI film prepared from HCl(aq), HClO(4)(aq), and H2SO4(aq), respectively. PANI film (260 nm) prepared from H2SO4(aq) revealed fiberlike morphology, and compared to PANI films prepared from HCl(aq) and HClO4(aq) with similar thickness, it has higher average nanoscale conductivity but lower bulk conductivity. This result could be direct evidence which supports that the bulk conductivity of PANI depended on the carriers hopping between the conducting domains.

Crops and food security--experiences and perspectives from Taiwan.

Food security is an important issue that is of concern for all countries around the world. There are many factors which may cause food insecurity including increasing demand, shortage of supply, trade condition, another countries' food policy, lack of money, high food and oil prices, decelerating productivity, speculation, etc. The food self-sufficiency ratio of Taiwan is only 30.6% weighted by energy in 2007. Total agriculture imports and cereals have increased significantly due to the expansion of livestock and fishery industries and improve living standard. The agriculture sector of Taiwan is facing many challenges, such as: low level of food self-sufficiency, aging farmers, large acreage of set-aside farmlands, small scale farming, soaring price of fertilizers, natural disasters accelerated by climate change, and rapid changes in the world food economy. To cope with these challenges, the present agricultural policy is based on three guidelines: "Healthfulness, Efficiency, and Sustainability." A program entitled "Turning Small Landlords into Large Tenants" was launched to make effective use of idle lands. Facing globalization and the food crisis, Taiwan will secure stable food supply through revitalization of its set-aside farmlands and international markets, and provide technical assistance to developing countries, in particular for staple food crops.