Supramolecular Enhancement of Electrochemical Nitrate Reduction Catalyzed by Cobalt Porphyrin Organic Cages for Ammonia Electrosynthesis in Water.

The electrochemical nitrate (NO ) reduction reaction (NO RR) to ammonia (NH ) represents a sustainable approach for denitrification to balance global nitrogen cycles and an alternative to traditional thermal Haber-Bosch processes. Here, we present a supramolecular strategy for promoting NH production in water from NO RR by integrating two-dimensional (2D) molecular cobalt porphyrin (CoTPP) units into a three-dimensional (3D) porous organic cage architecture. The porphyrin box CoPB-C8 enhances electrochemical active site exposure, facilitates substrate-catalyst interactions, and improves catalyst stability, leading to turnover numbers and frequencies for NH production exceeding 200,000 and 56 s , respectively.

Porosity as a Design Element for Developing Catalytic Molecular Materials for Electrochemical and Photochemical Carbon Dioxide Reduction.

The catalytic reduction of carbon dioxide (CO ) using sustainable energy inputs is a promising strategy for upcycling of atmospheric carbon into value-added chemical products. This goal has inspired the development of catalysts for selective and efficient CO conversion using electrochemical and photochemical methods. Among the diverse array of catalyst systems designed for this purpose, 2D and 3D platforms that feature porosity offer the potential to combine carbon capture and conversion.

Synergistic Porosity and Charge Effects in a Supramolecular Porphyrin Cage Promote Efficient Photocatalytic CO Reduction.

We present a supramolecular approach to catalyzing photochemical CO reduction through second-sphere porosity and charge effects. An iron porphyrin box (PB) bearing 24 cationic groups, FePB-2(P), was made via post-synthetic modification of an alkyne-functionalized supramolecular synthon. FePB-2(P) promotes the photochemical CO reduction reaction (CO RR) with 97 % selectivity for CO product, achieving turnover numbers (TON) exceeding 7000 and initial turnover frequencies (TOF ) reaching 1400 min .

Multifunctional Charge and Hydrogen-Bond Effects of Second-Sphere Imidazolium Pendants Promote Capture and Electrochemical Reduction of CO in Water Catalyzed by Iron Porphyrins.

Microenvironments tailored by multifunctional secondary coordination sphere groups can enhance catalytic performance at primary metal active sites in natural systems. Here, we capture this biological concept in synthetic systems by developing a family of iron porphyrins decorated with imidazolium (im) pendants for the electrochemical CO reduction reaction (CO RR), which promotes multiple synergistic effects to enhance CO RR and enables the disentangling of second-sphere contributions that stem from each type of interaction. Fe-ortho-im(H), which poises imidazolium units featuring both positive charge and hydrogen-bond capabilities proximal to the active iron center, increases CO binding affinity by 25-fold and CO RR activity by 2000-fold relative to the parent Fe tetraphenylporphyrin (Fe-TPP).

Genetic analysis of the ZNF804A gene in Mexican patients with schizophrenia, schizoaffective disorder and bipolar disorder.

Background: Evidence suggests that schizophrenia (SCZ), schizoaffective disorder (SAD) and bipolar disorder (BPD) share genetic risk variants. ZNF804A gene has been associated with these disorders in different populations. GWAS and candidate gene studies have reported association between the rs1344706 A allele with SCZ, SAD and BPD in European and Asian populations.

Distinctive prokaryotic microbiomes in sympatric plant roots from a Yucatan cenote.

Objective: Cenotes are flooded caves in Mexico's Yucatan peninsula. Many cenotes are interconnected in an underground network of pools and streams forming a vast belowground aquifer across most of the peninsula. Many plants in the peninsula grow roots that reach the cenotes water and live submerged in conditions similar to hydroponics.

Photoinduced Terminal Hydride of [FeFe]-Hydrogenase Biomimetic Complexes.

The active site of the [FeFe]-hydrogenase ([FeFe]-Hase) has a bridging carbonyl ligand and a terminal hydride in the key H-cluster intermediate H. However, nearly all of the synthetic mimics reported, so far, prefer a hydride bridging the two irons, and only few mimics with a terminal hydride were achieved by tuning the steric effects of bulky diphosphine ligands. Moreover, although intermediates with either a terminal hydride or a protonated bridging thiolate ligand were proposed to exist during protonation processes or hydrogen exchange in the [FeFe]-Hase mimic, [Fe(μ-pdt)(μ-H)(CO)PMe)] (), only bridging hydrides were observed by time-resolved IR spectroscopy.

Role of porcine serum haptoglobin in the host-parasite relationship of Taenia solium cysticercosis.

Human and porcine cysticercosis is a parasitic disease caused by the larval stage (cysts) of the tapeworm Taenia solium. Cysts may live in several host tissues such as skeletal muscle or brain. We have previously described the presence of host haptoglobin (Hp) and hemoglobin (Hb) in different protein extracts of the T.

Genetic variation of North American Triatomines (Insecta: Hemiptera: Reduviidae): initial divergence between species and populations of Chagas disease vector.

The triatomines vectors of Trypanosoma cruzi are principal factors in acquiring Chagas disease. For this reason, increased knowledge of domestic transmission of T. cruzi and control of its insect vectors is necessary.

Entomological indices, feeding sources, and molecular identification of Triatoma phyllosoma (Hemiptera: Reduviidae) one of the main vectors of Chagas disease in the Istmo de Tehuantepec, Oaxaca, Mexico.

The purpose of this study was to conduct an entomological analysis, determination of feeding sources, and molecular identification of triatomines in five communities of the Istmo de Tehuantepec, Oaxaca. The only found species in two of five searched communities (San Mateo del Mar and Tehuantepec City) was Triatoma phyllosoma. Colonization indices were high in both communities.

Natural crossbreeding between sympatric species of the phyllosoma complex (Insecta: Hemiptera: Reduviidae) indicate the existence of only one species with morphologic and genetic variations.

The nucleotide sequences of the cytochrome B gene and the antennal phenotypes were analyzed for the following triatomine species: Triatoma longipennis, Triatoma pallidipennis, and Triatoma picturata, which belong to the Phyllosoma complex. These species inhabit sympatric areas from Talpa de Allende, Autlan de Navarro, and Teocuitatlan de Corona in Jalisco, Mexico. Molecular marker analysis showed that the sympatric individuals are the natural crossbred descendents of different individuals living in close proximity in these natural areas that resulted in mixed populations.

Evolutionary history of a prominent North American warbler clade: the Oporornis-Geothlypis complex.

The avian genera Oporornis and Geothlypis are thought to represent a single lineage of closely related New World wood-warbler (AOU Family Parulidae) species. Phylogenetic relationships within this assemblage have not yet been addressed using molecular genetic methods. We used sequence data from three mitochondrial (mtDNA) genes (cytochrome b, ND2, and control region) to reconstruct an hypothesis of relationships for this group.

Two Triatoma dimidiata clades (Chagas disease vector) associated with different habitats in southern Mexico and Central America.

Triatoma dimidiata is the only reported Chagas disease vector in Campeche, Mexico. The purpose of this study was to determine the genetic variability of vectors from Campeche coastal and rain forest areas and establish a phylogenetic relationship with other T. dimidiata populations by analyzing the internal transcribed spacer-2 (ITS-2) region.

The genome project of Taenia solium.

We have constituted a consortium of key laboratories at the National Autonomous University of Mexico to carry out a genomic project for Taenia solium. This project will provide powerful resources for the study of taeniasis/cysticercosis, and, in conjunction with the Echinococcus granulosus and Echinococcus multilocularis genome project of expressed sequence tags (ESTs), will mark the advent of genomics for cestode parasites. Our project is planned in two consecutive stages.