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Anion receptors employing two distinct sensory mechanisms are rare. Herein, we report the first examples of halogen‐bonding porphyrin BODIPY [2]rotaxanes capable of both fluorescent and redox electrochemical sensing of anions. 1H NMR, UV/visible and electrochemical studies revealed rotaxane axle triazole group coordination to the zinc(II) metalloporphyrin‐containing macrocycle component, serves to preorganise the rotaxane binding cavity and dramatically enhances anion binding affinities. Mechanically bonded, integrated‐axle BODIPY and macrocycle strapped metalloporphyrin motifs enable the anion recognition event to be sensed by the significant quenching of the BODIPY fluorophore and cathodic perturbations of the metalloporphyrin P/P+. redox couple., The first examples of porphyrin‐BODIPY halogen bonding [2]rotaxanes have been prepared according to an active metal template strategy. Capitalising on the augmented anion affinities by virtue of axle triazole ligation to macrocyclic zinc(II) metalloporphyrin, the incorporation of fluorogenic BODIPY and redox‐active porphyrin transducing groups allows dual‐channel sensing of anions by quenching BODIPY emission and through cathodic perturbations of porphyrin oxidation redox couples.

Hydrogen sulfide (H₂S) plays a crucial signalling role in a variety of physiological systems, existing as the hydrosulfide anion (HS⁻) at physiological pH. Combining the potency of halogen bonding (XB) for anion recognition in water with coumarin fluorophore incorporation in acyclic host structural design, the first XB receptors to bind and, more importantly, sense the hydrosulfide anion in pure water in a reversible chemosensing fashion are demonstrated. The XB receptors exhibit characteristic selective quenching of fluorescence upon binding to HS⁻. Computational DFT and molecular dynamics simulations in water corroborate the experimental anion binding observations, revealing the mode and nature of HS⁻ recognition by the XB receptors. published

Hydrogen sulfide (H2S) plays a crucial signalling role in a variety of physiological systems, existing as the hydrosulfide anion (HS−) at physiological pH. Combining the potency of halogen bonding (XB) for anion recognition in water with coumarin fluorophore incorporation in acyclic host structural design, the first XB receptors to bind and, more importantly, sense the hydrosulfide anion in pure water in a reversible chemosensing fashion are demonstrated. The XB receptors exhibit characteristic selective quenching of fluorescence upon binding to HS−. Computational DFT and molecular dynamics simulations in water corroborate the experimental anion binding observations, revealing the mode and nature of HS− recognition by the XB receptors., Reversible chemosensing of hydrosulfide (HS−) in pure water is demonstrated using halogen bonding (XB) fluorescent hosts. The XB receptors exhibit characteristic selective quenching of fluorescence upon binding HS− whereas the hydrogen bonding receptor analogues proved incapable of functioning as chemosensors under aqueous conditions.

Shortly after World War II a Communist guerrilla army, the Hukbong Magpalayang Bayan (HMB), or People's Liberation Army, became a serious threat to the new Philippine Republic. The Huks, as they are commonly known, controlled large parts of the sugar cane and rice growing areas of Central Luzon and carried out military and political operations in other parts of the islands. Like their Communist counterparts in Vietnam and Malaya, the Huks began as an anti-Japanese guerrilla army. In fact, Huk originally referred to Hukbalahap, a contraction of a phrase meaning People's Army Against the Japanese. As the military arm of the Communist Party, however, their ambitions always exceeded mere anti-Japanese activities. After the Japanese defeat, successive Philippine governments wrestled with the problem of eliminating the Huks. Policies of coercion failed because the Philippine Army and Constabulary were not up to the task. Policies of conciliation failed because the demands of the Huks were regarded as unreasonable. By 1949 it became clear that the issues dividing the Huks and the government would have to be settled by force. Following the allegedly fraudulent election of President Quirino in 1949 the Huks gained steadily. By 1950 large unit raids were common and a full-scale attack on Manila was envisioned for 1951. Before that time arrived, however, the tide had begun to turn. Under the new Defense Secretary, Ramon Magsaysay, the Constabulary and Army were reorganized, and by the early 1950s the Huks were on the run, one of the most dramatic events being the surrender of former Huk Supremo Luis Taruc in May 1954.1 Despite the decimation of Huk units in Northern and Southern Luzon, Panay, and other regions, the movement survived and persists to this day especially in the part of

Often in a civil war the regional divisions of the nation are so striking as to reveal immediately the source of the conflict and the cleavages in society. The American Civil War is an excellent example. It frequently happens, however, that the regional divisions are not so dramatic or well-defined, thus disclosing little about the nature of the struggle taking place. The Vietnamese war, especially prior to the substantial involvement of foreign troops, appears to be one of these situations. It seems as if both parties to the conflict are to be found almost everywhere in the country. There is not a province of South Vietnam in which the Government of Vietnam (GVN) and Viet Cong (VC) do not each exert some noticeable degree of influence. This piebald arrangement of governmentand rebel-held areas allows no easy interpretation. Perhaps the only obvious distinction between the two areas is a strong tendency for the government to control larger towns; beyond this, differences are less evident. One way of determining the important differences between rebel and government areas is to compare data on the extent of GVN control in a province with the social, economic, cultural and topographic characteristics of the province. This paper is a summary of such a quantitative analysis recently carried out by the author.' A linear multiple regression was run across 26 South Vietnamese provinces (highland provinces were excluded) with GVN control as the dependent variable and a large number of potentially important social, economic and other measurements as independent variables. GVN control is defined to be the percentage of hamlets in a province classified as government controlled according to a detailed map appearing in the Los Angeles Times, December 26, 1965. According to the Times, this map is derived from United States Government sources. It turns out that each of six independent variables possesses a statistically significant influence upon control. Together

T HE productivity and wages of workers in any nation depend upon the quality of the workers and the relative quantities of complementary factors of production. In recent empirical work on the estimation of cross-national production functions it has generally been assumed that labor is homogeneous, and complemented by a single factor of production, capital. Reference is made particularly to the pioneering article by Arrow, Chenery, Minhas, and Solow, and the monograph by Minhas.' These assumptions, it turns out, lead to a very incomplete explanation of international differences in labor productivity and wages, and totally ignore the systematic variation of wages over industries. This simple capital-labor model, Professor Leontief argues, also leads to incorrect predictions about international specialization because labor quality differs substantially over nations.2 A natural step is to introduce labor quality into the analysis. Attempts in this direction face one major obstacle the absence of comparable data measuring the skills of workers in different countries. Consequently, we do not have at hand a direct test of the proposition that a capital-labor model augmented by the assumption of heterogeneous labor can account fullv for international differences in labor Droductivity and wages. Nevertheless, it will be shown that a more general model incorporating two imperfectly substitutable types of labor can offer a significant improvement in explaining the over-all pattern of labor productivity, wages, and international trade among developed countries and within manufacturing industries.