A brief review on coal reserves, production and possible non-power uses: The case of Mexico.

Coal has been a valuable natural resource for Mexico not just for its relative abundance but for its critical role in the development of the steel and energy industries. It has been also important in the socioeconomic context of the northeast of the country. However, since years ago, coal mining is facing a transition due to the emergence of new energy sources and the public concern about global warming. A brief review on coal reserves, production and possible non-power uses was carried out to provide insight on the reserves in a global context, extraction patterns and alternatives that the Mexican coal industry has to evolve. For this purpose, Mexican coal reserves were overviewed and contextualized at a global level and total coal production figures from 1970 to 2021 were analyzed to identify fluctuations and differences in the amounts produced between coking and non-coking coal. Further, rare earth elements, carbon fiber and humic acid from coal were briefly reviewed with the aim of initiating a debate on the high value-added products that can be obtained and the technologies that can be adopted to develop the coal industry of Mexico. Coal proven reserves in Mexico are of 1211 million tonnes and, from 1970 to 2021, 428.11 million tonnes have been produced. Of the total cumulative production, 68.8% corresponds to non-coking coal and 31.2% to coking coal.

Hierarchical settlement behaviours of coral larvae to common coralline algae.

Natural regeneration of degraded reefs relies on the recruitment of larvae to restore populations. Intervention strategies are being developed to enhance this process through aquaculture production of coral larvae and their deployment as spat. Larval settlement relies on cues associated with crustose coralline algae (CCA) that are known to induce attachment and metamorphosis. To understand processes underpinning recruitment, we tested larval settlement responses of 15 coral species, to 15 species of CCA from the Great Barrier Reef (GBR). CCA in the family Lithophyllaceae were overall the best inducer across most coral species, with Titanoderma cf. tessellatum being the most effective species that induced at least 50% settlement in 14 of the coral species (mean 81%). Taxonomic level associations were found, with species of Porolithon inducing high settlement in the genus Acropora; while a previously understudied CCA, Sporolithon sp., was a strong inducer for the Lobophyllidae. Habitat-specific associations were detected, with CCA collected from similar light environment as the coral inducing higher levels of settlement. This study revealed the intimate relationships between coral larvae and CCA and provides optimal coral-algal species pairings that could be utilized to increase the success of larval settlement to generate healthy spat for reef restoration.

Dataset for the thermodynamic simulation of the dissolution behaviour of elemental tellurium and tellurium dioxide in alkaline cyanide solutions.

It is necessary to simulate the thermodynamics of the Te/TeO2-CN-H2O systems to interpret the dissolution behaviour of elemental tellurium and tellurium dioxide in alkaline cyanide solutions. Below are the data employed to simulate the equilibrium diagrams presented in the article entitled "Dissolution behaviour of elemental tellurium and tellurium dioxide in alkaline cyanide solutions". Most of the reactions are available in the Hydra database of MEDUSA© software along with their logarithms to the base 10 of the equilibrium constants (i.e., log K). However, it was complemented with the log K of some important reactions (e.g., which describes the formation of H2TeO3). Log K values were calculated form the ΔG°f reported in the scientific literature. The databases reported can be used to compare the equilibrium constant values, replicate the diagrams presented in the cited article, and simulate other aqueous systems (e.g., those employing alternative lixiviant agents as thiosulfate, thiourea, etc.).

Birds vs bricks: Patterns of species diversity in response to urbanization in a Neotropical Andean city.

Urbanization is currently one the most important causes of biodiversity loss. The Colombian Andes is a well-known hotspot for biodiversity, however, it also exhibit high levels of urbanization, making it a useful site to document how species assemblages respond to habitat transformation. To do this, we compared the structure and composition of bird assemblages between rural and urban habitats in Armenia, a medium sized city located in the Central Andes of Colombia. In addition, we examined the influence of urban characteristics on bird species diversity within the city of Armenia. From September 2016 to February 2017 we performed avian surveys in 76 cells (250 x 250 m each) embedded within Armenia city limits; and in 23 cells (250 x 250 m each) in rural areas around Armenia. We found that bird diversity was significantly lower in urban habitats than in rural habitats, and differed in species composition by 29%. In urban cells, with higher abiotic noise intensity and higher impervious surface area, we found lower bird diversity than that in urban cells with higher guadual (Guadua angustifolia patches), and forested surface areas. We did not find segregation of urban cells according to the species composition, although additional bird surveys inside urban forests remnant are needed to be more conclusive about this aspect. Altogether, our results highlight the importance of green areas embedded within cities to conserve bird diversity through reducing the ecological impact of urbanization on avian biodiversity.

First-line single-agent panitumumab in frail elderly patients with wild-type KRAS metastatic colorectal cancer and poor prognostic factors: A phase II study of the Spanish Cooperative Group for the Treatment of Digestive Tumours.

BACKGROUND: Frail elderly patients with metastatic colorectal cancer (mCRC) are not candidates for chemotherapy. Monotherapy with anti-epidermal growth factor receptor (EGFR) monoclonal antibodies may be an option for these patients with few systemic toxic effects. PATIENTS AND METHODS: Single-arm, multicentre, phase II trial including patients ⩾ 70y ears with wild-type (WT) KRAS (exon 2) mCRC, Eastern Cooperative Oncology Group (ECOG) status ⩽ 3, KPC (Köhne Prognostic Classification)--defined intermediate or high risk status, frailty and/or ineligibility for chemotherapy. Patients received panitumumab until progression or unacceptable toxicity. The primary end-point was progression free survival (PFS) rate at 6 months. RESULTS: The study included 33 patients (intention-to-treat (ITT) population). Median age: 81 years; sex: 66.7% male; high-risk KPC status: 45.4%. Median treatment duration was 14 weeks and 6-month PFS rate was 36.4% (95% confidence interval (CI): 20.0-52.8). The objective response rate: 9.1% (95% CI: 0-18.9) (all partial responses), and there were 18 stable diseases (54.5%). Median PFS was 4.3 months (95% CI: 2.8-6.4) and median overall survival (OS) was 7.1 months (95% CI: 5.0-12.3). There were no deaths or grade 4-5 adverse events (AEs) related to panitumumab and the most common grade 3-related AE was rash acneiform (15.2%). A significant association between clinical response and RAS status was observed (P=0.037). In the WT RAS subgroup (WT exons 2, 3, and 4 of KRAS and NRAS, N = 15), 6-month PFS rate was 53.3% (95% CI: 30.1-75.2) and median PFS and OS were 7.9 and 12.3 months, respectively. CONCLUSIONS: Single-agent panitumumab is active and well tolerated and may be a therapeutic option for high-risk frail elderly patients with WT RAS tumours considered not candidates for chemotherapy (clinicaltrials.gov identifier NCT01126112).

Cannabis use and age at onset of psychosis: further evidence of interaction with COMT Val158Met polymorphism.

OBJECTIVE: To examine, in a sample of young psychiatric patients, (n = 157, mean age 17.01 years (SD = 3.6)) whether i) age at first cannabis use and age at emergence of psychiatric disorders are related and ii) such a relationship is modulated by the Val158Met polymorphism in the COMT gene. METHOD: Cannabis use profiles and COMT Val158Met genotypes were obtained from 80 inpatients with schizophrenia-spectrum disorders and 77 inpatients with other non-psychotic disorders. RESULTS: First, age at first cannabis use correlates with age at onset in both schizophrenia-spectrum and other psychiatric disorder groups: those who started using cannabis earlier had an earlier age at onset of psychiatric disorders. Second, the distribution of the Val158Met genotypes was not different either between diagnosis groups or between cannabis users and non-users. Third, an interaction between Val158Met genotypes and cannabis use was observed specifically on age at emergence of psychotic disorders, with Val/Val genotype carriers showing an earlier age at onset than Met carriers. CONCLUSION: Our results suggest the importance of brain maturation timing in which exposure to cannabis occurs. The COMT Val158Met genotype seems to modulate the association between cannabis and age at onset of psychotic disorders. These results are consistent with previous studies.

Ocean acidification causes bleaching and productivity loss in coral reef builders.

Ocean acidification represents a key threat to coral reefs by reducing the calcification rate of framework builders. In addition, acidification is likely to affect the relationship between corals and their symbiotic dinoflagellates and the productivity of this association. However, little is known about how acidification impacts on the physiology of reef builders and how acidification interacts with warming. Here, we report on an 8-week study that compared bleaching, productivity, and calcification responses of crustose coralline algae (CCA) and branching (Acropora) and massive (Porites) coral species in response to acidification and warming. Using a 30-tank experimental system, we manipulated CO(2) levels to simulate doubling and three- to fourfold increases [Intergovernmental Panel on Climate Change (IPCC) projection categories IV and VI] relative to present-day levels under cool and warm scenarios. Results indicated that high CO(2) is a bleaching agent for corals and CCA under high irradiance, acting synergistically with warming to lower thermal bleaching thresholds. We propose that CO(2) induces bleaching via its impact on photoprotective mechanisms of the photosystems. Overall, acidification impacted more strongly on bleaching and productivity than on calcification. Interestingly, the intermediate, warm CO(2) scenario led to a 30% increase in productivity in Acropora, whereas high CO(2) lead to zero productivity in both corals. CCA were most sensitive to acidification, with high CO(2) leading to negative productivity and high rates of net dissolution. Our findings suggest that sensitive reef-building species such as CCA may be pushed beyond their thresholds for growth and survival within the next few decades whereas corals will show delayed and mixed responses.

Detection of coronary artery stenosis with power Doppler imaging.

BACKGROUND: Power Doppler is a new imaging method for detecting microbubbles during myocardial contrast echocardiography (MCE) based on the registration of variance resulting from ultrasound-induced nonlinear bubble behavior. We tested the hypothesis that power Doppler imaging can be used to quantify coronary stenoses. METHODS AND RESULTS: Three left anterior descending (LAD) coronary stenoses of varying severity were created in each of 9 open-chest dogs. MCE was performed by continuous intravenous infusion of a nitrogen-filled bilayer shell microbubble, PB127, during triggered power Doppler imaging at incremental pulsing intervals. MCE and radiolabeled microsphere measurements were made at baseline and during each stenosis, with and without adenosine stress. Videointensities in the LAD and left circumflex (LCx) beds were plotted against pulsing interval and fit to a previously described exponential function modeling microbubble destruction and replenishment, which was used to derive parameters of bubble velocity (beta) and peak plateau videointensity (A). Contrast defects matching the location of radiolabeled microsphere hypoperfusion were clearly seen, without need for image processing. The product of beta and A was linearly related to LAD/LCx flow (r=0.90, P<0.0001) and inversely related to stenosis gradient (r=-0.70, P<0.0001). Endocardial/epicardial flow ratios were visualized and quantifiable. CONCLUSIONS: As with B-mode harmonics, a model of microbubble destruction/replenishment can be applied to power Doppler data as a means to detect a broad range of stenoses. Image clarity and the lack of attenuation or requirement for background subtraction are additional advantages of this imaging approach. Power Doppler MCE imaging holds promise for the detection of coronary artery disease.

Ultrasound-enhanced thrombolysis at 20 kHz with air-filled and perfluorocarbon-filled contrast bispheres.

BACKGROUND: Ultrasound (US) at low frequencies has been shown to enhance clot lysis by itself and in the presence of urokinase (UK). The comparative effects of air-filled versus perfluorocarbon-filled polymer bispheres in enhancing this effect have not been previously demonstrated. METHODS: Freshly drawn human blood was incubated at 37 degrees C for 2 hours, and the subsequent formed clot was dried and weighed. It was then exposed to saline control, saline + UK (10,000 IU), saline + UK + US, saline + UK + US + low shell-strength polymer bispheres (PB1), saline + UK + US + high shell-strength polymer bispheres (PB2), and perfluorocarbon-filled high shell-strength polymer bipsheres (PB3) for a total of 6 minutes. Clots were removed and weighed to determine the percentage of thrombolysis. RESULTS: The percentage of clot lysis for each study group was as follows: saline 18.5% +/- 4%, US alone 22.2% +/- 5%, UK alone 21.9% +/- 4%, US+UK 32.2% +/- 8% (P <.05 compared with UK alone), US+UK+PB1 36.9% +/- 8%, US+UK+PB2 34.3% +/- 8%, and US+UK+PB3 45.0% +/- 11% (P <.05 compared with US+UK, P <.05 compared with US+UK+PB2). CONCLUSION: Ultrasound at 20 kHz significantly enhances clot lysis. The addition of perfluorocarbon-filled bispheres increased this effect more significantly than did the addition of air-filled polymer bispheres.

Unidentified open reading frames in the genome of Methanococcus jannaschii are similar in sequence to an archaebacterial gene for tRNA nucleotidyltransferase.

The protein sequence of ATP/CTP:tRNA nucleotidyltransferase (cca) from Sulfolobus shibatae was used to search open reading frames in the genome of Methanococcus jannaschii. Translations of two unidentified open reading frames showed significant sequence similarity to portions of the Sulfolobus cca protein. When the two open reading frames were joined together, the expanded open reading frame was similar in sequence to the entire Sulfolobus cca protein and displayed features of the active site signature sequence proposed for members of class I enzymes within the superfamily of nucleotidyltransferases (Yue et al., 1996, RNA 2, 895-908). A possible UUG start codon was identified based on significant sequence similarity of the resulting amino-terminal region to that of Sulfolobus, and on a six-base complementarity between an adjacent upstream sequence and Methanococcus 16S rRNA.

Quasisteady behavior of pulsatile, confined, counterflowing jets: implications for the assessment of mitral and tricuspid regurgitation.

Mitral and tricuspid regurgitation create turbulent jets within the atria. Clinically, for the purpose of estimating regurgitant severity, jet size is assumed to be proportional to peak jet flow rate and regurgitant volume. Unfortunately, the relationship is more complex because the determinants of jet size include interactions between jet pulsatility, jet momentum, atrial width, and the velocity of ambient atrial counterflows. These effects on fluorescent jet penetration were measured using an in vitro simulation. Both steady and pulsatile jets were driven into an opposing counterflow velocity field peak jet length (Ljp) measurements made as a function of (1) peak orifice velocity (Ujp), (2) the time required for the jet to accelerate from zero to peak velocity and begin to decelerate (Tjp), (3) jet orifice diameter (Dj), (4) counterflow velocity (Uc), and (5) counterflow tube diameter (Dc). A compact mathematical description was developed using dimensional analysis. Results showed that peak jet length was a function of the counterflow tube diameter, the ratio of peak jet to counterflow momentum, (Mjp/Mc) = (U2jpD2j)/(U2cD2c), and a previously undescribed jet pulsatility parameter, the pulsatility index (PI), PI = D2c/(TjpUjpDj). For the same jet orifice flow conditions, jet penetration decreased as chamber diameter decreased, as the jet PI increased, and as the momentum ratio decreased. These interactions provide insight into why regurgitant jet size is not always a good estimate of regurgitant severity.

Atrial inflow can alter regurgitant jet size: in vitro studies.

Recent studies have attempted to predict the severity of regurgitant lesions from color Doppler jet size, which is a function of orifice momentum for free jets. Jets of mitral and tricuspid regurgitation, however, are opposed by flows entering the atria. Despite their low velocities, these counterflows may have considerable momentum that can limit jet penetration. The purpose of this study was to address the hypothesis that such counterflow fields influence regurgitant jet size. Steady flow was driven through 2.4- and 5.1-mm-diameter circular orifices at 2 to 6 m/s. At a constant orifice velocity and flow rate, the velocity of a uniform counterflow field was varied from 5 to 30 cm/s. Jet dimensions were measured by both fluorescent dye visualization and Doppler color flow mapping. The results showed that despite its relatively low velocities, counterflow dramatically curtailed jet length and area. Jet dimensions were functions of the ratio of jet to counterflow momentum. Thus, atrial inflow may participate in determining jet size and can alter the relation between jet size and lesion severity in mitral and tricuspid regurgitation.