Control of Chemical Reaction Pathways by Light-Matter Coupling.

Because plasmonic metal nanostructures combine strong light absorption with catalytically active surfaces, they have become platforms for the light-assisted catalysis of chemical reactions. The enhancement of reaction rates by plasmonic excitation has been extensively discussed. This review focuses on a less discussed aspect: the induction of new reaction pathways by light excitation. Through commentary on seminal reports, we describe the principles behind the optical modulation of chemical reactivity and selectivity on plasmonic metal nanostructures. Central to these phenomena are excited charge carriers generated by plasmonic excitation, which modify the energy landscape available to surface reactive species and unlock pathways not conventionally available in thermal catalysis. Photogenerated carriers can trigger bond dissociation or desorption in an adsorbate-selective manner, drive charge transfer and multielectron redox reactions, and generate radical intermediates. Through one or more of these mechanisms, a specific pathway becomes favored under light. By improved control over these mechanisms, light-assisted catalysis can be transformational for chemical synthesis and energy conversion.

Roadmap on quantum nanotechnologies.

Quantum phenomena are typically observable at length and time scales smaller than those of our everyday experience, often involving individual particles or excitations. The past few decades have seen a revolution in the ability to structure matter at the nanoscale, and experiments at the single particle level have become commonplace. This has opened wide new avenues for exploring and harnessing quantum mechanical effects in condensed matter. These quantum phenomena, in turn, have the potential to revolutionize the way we communicate, compute and probe the nanoscale world. Here, we review developments in key areas of quantum research in light of the nanotechnologies that enable them, with a view to what the future holds. Materials and devices with nanoscale features are used for quantum metrology and sensing, as building blocks for quantum computing, and as sources and detectors for quantum communication. They enable explorations of quantum behaviour and unconventional states in nano- and opto-mechanical systems, low-dimensional systems, molecular devices, nano-plasmonics, quantum electrodynamics, scanning tunnelling microscopy, and more. This rapidly expanding intersection of nanotechnology and quantum science/technology is mutually beneficial to both fields, laying claim to some of the most exciting scientific leaps of the last decade, with more on the horizon.

Nuclease activity via self-activation and anticancer activity of a mononuclear copper(II) complex: novel role of the tertiary butyl group in the ligand frame.

The copper complex [Cu((t)BuPhimp)(Cl)] (1) derived from tridentate ligand (t)BuPhimpH having N(2)O donors was synthesized, and its molecular structure was determined. A phenoxyl radical complex was generated in solution at room temperature using Ce(IV). The nuclease and anticancer activities of 1 were investigated. The roles of the tert-butyl group and singlet oxygen in the DNA cleavage activity were also discussed.

A perturbative approach to study information communication in brain networks.

How communication among neuronal ensembles shapes functional brain dynamics is a question of fundamental importance to neuroscience. Communication in the brain can be viewed as a product of the interaction of node activities with the structural network over which these activities flow. The study of these interactions is, however, restricted by the difficulties in describing the complex dynamics of the brain. There is thus a need to develop methods to study these network-dynamical interactions and how they impact information flow, without having to ascertain dynamics a priori or resort to restrictive analytical approaches. Here, we adapt a recently established network analysis method based on perturbations, it to a neuroscientific setting to study how information flow in the brain can raise from properties of underlying structure. For proof-of-concept, we apply the approach on in silico whole-brain models. We expound on the functional implications of the distributions of metrics that capture network-dynamical interactions, termed net influence and flow. We also study the network-dynamical interactions at the level of resting-state networks. An attractive feature of this method is its simplicity, which allows a direct translation to an experimental or clinical setting, such as for identifying targets for stimulation studies or therapeutic interventions.

In this work, we use controlled perturbations in silico to identify regions that influence and mediate information flow in active brain networks. Conventional approaches of identifying such regions require the extensive analytical treatment of mathematical models describing node dynamics, thus restricting its scope only to systems where such models have been defined. The presented formalism can identify regions of dynamical and functional importance by simply measuring responses to perturbations, and can thus be applied at any scale where regions can be perturbed, and without any prerequisite information about node dynamics. Furthermore, the relation of metrics to interregional communication, functional capabilities, and structure-function mapping in general affords them considerable practical importance, especially for identifying targets for therapeutic interventions.

Singh's verbal autopsy questionnaire for the assessment of causes of death, social autopsy, tobacco autopsy and dietary autopsy, based on medical records and interview.

INTRODUCTION: The exact causes of death in India are not known because autopsy studies are difficult to conduct due to religious considerations. There are rapid changes in diet and lifestyle amongst social classes causing changes in the pattern of risk factors and mortality. In the present study, we attempt to develop a verbal autopsy questionnaire based on medical records and interview of a family member, for the assessment of causes of death, social class, tobacco consumption and dietary intakes among urban decedents in north India. METHODS: For the period 1999-2001, we studied the randomly selected records of death of 2222 (1385 men and 837 women) decedents, aged 25-64 years, out of 3034 death records overall from the records at the Municipal Corporation, Moradabad. Families of these decedents were contacted individually to find out the causes of death, by scientist- administered, informed-consented, verbal autopsy questionnaire, completed with the help of the spouse and local treating doctor practicing in the appropriate health care region. Clinical data and causes of death were assessed by a questionnaire based on available hospital records and a modified WHO verbal autopsy questionnaire. Dietary intakes of the dead individuals were estimated by finding out the food intake of the spouse from 3-day dietary diaries and by asking probing questions about differences in food intake by the decedents. Tobacco consumption of the victim was studied by a questionnaire administered to family members. Social classes were assessed by a questionnaire based on attributes of per capita income, occupation, education, housing and ownership of consumer luxury items in the household. The diagnoses of overweight and obesity were based on the new WHO and International College of Nutrition criteria. RESULTS: Cardiac diseases (23.4%, n = 520) including coronary artery disease (10%), valvular heart disease (7.2%, n = 160), diabetic heart disease (2.2%, n = 49), sudden cardiac death and inflammatory cardiac disease, each (2.0%, n = 44) were the most common causes of deaths as reported using the modified verbal autopsy questionnaire. Brain diseases including stroke (7.8%, n = 175) and inflammatory brain disease were reported amongst 1.9% (n = 42) victims.Thus, NCDs (37.0%, n = 651); circulatory diseases (31.2%, n = 695) including stroke and cardiac diseases, and malignant neoplasms (5.8%, n = 131) emerged as the most common causes of death. Injury and accidents (14.0%, n = 313) including fire, falls and poisonings were also common. Miscellaneous causes of death were observed amongst 8.5% (n = 189) of victims. Pregnancy and perinatal causes (0.72%, n = 15) were not commonly recorded in our study. Renal diseases (11.2%, n = 250), pulmonary diseases (22.3%, n = 495) and liver diseases (4.8%, n =107) were also commonly recorded causes of death. It is clear that causes of death related to various body systems can be more accurately assessed by the modified verbal autopsy questionnaire. Circulatory diseases as the cause of mortality were significantly more common among higher social classes (1-3) than in lower social classes (4 and 5) who died more often, due to infections. Death due to coronary disease, stroke, hypertension, diabetes and obesity were significantly more common among higher social classes 1-3 and among victims with higher body mass index (BMI) compared to social class 4 and 5 who had lower BMI. CONCLUSIONS: This study indicates that causes of death, social class, tobacco and dietary intakes, can be accurately assessed by a modified verbal autopsy questionnaire based on medical records and by interview of family members. Circulatory diseases, injury-accidents and maligant diseases have become the major causes of death in India, apart from infections.

A rich catalog of C-C bonded species formed in CO2 reduction on a plasmonic photocatalyst.

The understanding and rational design of heterogeneous catalysts for complex reactions, such as CO2 reduction, requires knowledge of elementary steps and chemical species prevalent on the catalyst surface under operating conditions. Using in situ nanoscale surface-enhanced Raman scattering, we probe the surface of a Ag nanoparticle during plasmon-excitation-driven CO2 reduction in water. Enabled by the high spatiotemporal resolution and surface sensitivity of our method, we detect a rich array of C1-C4 species formed on the photocatalytically active surface. The abundance of multi-carbon compounds, such as butanol, suggests the favorability of kinetically challenging C-C coupling on the photoexcited Ag surface. Another advance of this work is the use of isotope labeling in nanoscale probing, which allows confirmation that detected species are the intermediates and products of the catalytic reaction rather than spurious contaminants. The surface chemical knowledge made accessible by our approach will inform the modeling and engineering of catalysts.

Case report of isolated congenital absence of right pulmonary artery with collaterals from coronary circulation.

Isolated unilateral absence of a proximal pulmonary main artery is a rare congenital lesion which is often associated with other cardiovascular abnormalities and a diverse clinical presentation. It is usually diagnosed in childhood. Patients who survive into adulthood is uncommon. We report a case of 46 year old hypertensive and obese female who presented with progressive dyspnea. She had features of pulmonary hypertension. The diagnosis was confirmed by CT pulmonary angiography which showed absence of right pulmonary artery and conventional pulmonary angiography which showed ipsilateral lung receiving collaterals from Right coronary artery and its branches. The purpose of this report is to highlight the fact that UAPA, although a rare entity, should be kept in mind in patients with unexplained PAH and prolonged respiratory symptoms unresponsive to routine treatment modalities.

Role of coenzyme Q10 (CoQ10) in cardiac disease, hypertension and Meniere-like syndrome.

Coenzyme Q10 (ubiquinone) is a mitochondrial coenzyme which is essential for the production of ATP. Being at the core of cellular energy processes it assumes importance in cells with high energy requirements like the cardiac cells which are extremely sensitive to CoQ10 deficiency produced by cardiac diseases. CoQ10 has thus a potential role for prevention and treatment of heart ailments by improving cellular bioenergetics. In addition it has an antioxidant, a free radical scavenging and a vasodilator effect which may be helpful in these conditions. It inhibits LDL oxidation and thus the progression of atherosclerosis. It decreases proinflammatory cytokines and decreases blood viscosity which is helpful in patients of heart failure and coronary artery disease. It also improves ischemia and reperfusion injury of coronary revascularisation. Significant improvement has been observed in clinical and hemodynamic parameters and in exercise tolerance in patients given adjunctive CoQ10 in doses from 60 to 200 mg daily in the various trials conducted in patients of heart failure, hypertension, ischemic heart disease and other cardiac illnesses. Recently it has been found to be an independent predictor of mortality in congestive heart failure. It has also been found to be helpful in vertigo and Meniere-like syndrome by improving the immune system. Further research is going on to establish firmly its role in the therapy of cardiovascular diseases.