Restricting Voting Rights in Modern America

The Supreme Court’s Shelby County v. Holder ruling invalidating Section 4(b) of the Voting Rights Act of 1965 is in part a product of efforts to resist further transformations to the traditional American institutional arrangements that have conferred advantages on whites, especially disproportionate political power. Those efforts in resistance are not likely to succeed in the long run. But they may embroil American elections and American governance in paralyzing conflicts for years to come.La décision de la Cour suprême dans l’arrêt Comté de Shelby c. Holder, invalidant la Section 4 (b) de la Loi sur les droits de vote de 1965, est en partie le produit d’une volonté de maintenir les avantages particulièrement disproportionnée des Blancs en matière de pouvoir politique et de résister à toutes les nouvelles tentatives transformation des arrangements institutionnels américains traditionnels. Ces efforts de résistance ne sont pas susceptibles de réussir sur le long terme. Mais ils peuvent entrainer les élections américaines et la gouvernance américaine dans des conflits paralysants pour les années à venir

NAD+-dependent DNA ligases of Mycobacterium tuberculosis and Streptomyces coelicolor

Sequencing of the genomes of Mycobacterium tuberculosis H37Rv and Streptomyces coelicolor A3(2) identified putative genes for an NAD+-dependent DNA ligase. We have cloned both open reading frames and overexpressed the protein products in Escherichia coli. In vitro biochemical assays confirm that each of these proteins encodes a functional DNA ligase that uses NAD+ as its cofactor. Expression of either protein is able to complement E. coli GR501, which carries a temperature-sensitive mutation in ligA. Thus, in vitro and in vivo analyses confirm predictions that ligA genes from M. tuberculosis and S. coelicolor are NAD+-dependent DNA ligases

Characterization of a temperature-sensitive DNA ligase from Escherichia coli

DNA ligases are essential enzymes in cells due to their ability to join DNA strand breaks formed during DNA replication. Several temperature-sensitive mutant strains of Escherichia coli, including strain GR501, have been described which can be complemented by functional DNA ligases. Here, it is shown that the ligA251 mutation in E. coli GR501 strain is a cytosine to thymine transition at base 43, which results in a substitution of leucine by phenylalanine at residue 15. The protein product of this gene (LigA251) is accumulated to a similar level at permissive and non-permissive temperatures. Compared to wild-type LigA, at 20 °C purified LigA251 has 20-fold lower ligation activity in vitro, and its activity is reduced further at 42 °C, resulting in 60-fold lower ligation activity than wild-type LigA. It is proposed that the mutation in LigA251 affects the structure of the N-terminal region of LigA. The resulting decrease in DNA ligase activity at the non-permissive temperature is likely to occur as the result of a conformational change that reduces the rate of adenylation of the ligase

Restricting Voting Rights in Modern America

The Supreme Court’s Shelby County v. Holder ruling invalidating Section 4(b) of the Voting Rights Act of 1965 is in part a product of efforts to resist further transformations to the traditional American institutional arrangements that have conferred advantages on whites, especially disproportionate political power. Those efforts in resistance are not likely to succeed in the long run. But they may embroil American elections and American governance in paralyzing conflicts for years to come.La décision de la Cour suprême dans l’arrêt Comté de Shelby c. Holder, invalidant la Section 4 (b) de la Loi sur les droits de vote de 1965, est en partie le produit d’une volonté de maintenir les avantages particulièrement disproportionnée des Blancs en matière de pouvoir politique et de résister à toutes les nouvelles tentatives transformation des arrangements institutionnels américains traditionnels. Ces efforts de résistance ne sont pas susceptibles de réussir sur le long terme. Mais ils peuvent entrainer les élections américaines et la gouvernance américaine dans des conflits paralysants pour les années à venir

Genetic and Genomic Strategies in Learning and Memory

Abstract: Learning and memory is a property of central importance in the nervous system, yet many of the molecular mechanisms for this behavior remain enshrouded in mystery. Despite the daunting nature of the problem, a number of complementary strategies have been employed to unravel the complexities of learning and memory, ranging from genetics to biochemistry. One of the most recent tools brought to bear in this area is genomics. Here, we review some of the most significant insights that have been so far obtained in learning and memory, and we suggest possible areas of future progress

How to make better use of physical properties in mineral exploration: The exploration site measurement

This paper is © 2019 Society of Exploration Geophysicists. The posting is available free of charge and its use is subject to the SEG terms and conditions: https://seg.org/Terms-of-UseIn recent years, there has been a growing awareness that a better understanding of physical property information is required in mineral exploration. As a consequence, there has been a strong push to collect more data and to use these data more intelligently. There are a multiplicity of reasons behind this impetus: geophysicists want more information about physical property data to enable better surveys to be planned and better interpretations to come from the data acquired and geologists want physical properties to provide addition information about the geology that might allow them to see variations in rocks that are not easy to see using traditional or more expensive methods (hand specimen examination, thin sections, lithogeochemistry, assays, etc.). If a hole is drilled on a geophysical target, then a physical property measurement of the core or the rocks surrounding the core can confirm if the target was intercepted and provides data that can be used to model the target response

A prospective evaluation of treatment with Selective Internal Radiation Therapy (SIR-spheres) in patients with unresectable liver metastases from colorectal cancer previously treated with 5-FU based chemotherapy

BACKGROUND: To prospectively evaluate the efficacy and safety of selective internal radiation (SIR) spheres in patients with inoperable liver metastases from colorectal cancer who have failed 5FU based chemotherapy. METHODS: Patients were prospectively enrolled at three Australian centres. All patients had previously received 5-FU based chemotherapy for metastatic colorectal cancer. Patients were ECOG 0–2 and had liver dominant or liver only disease. Concurrent 5-FU was given at investigator discretion. RESULTS: Thirty patients were treated between January 2002 and March 2004. As of July 2004 the median follow-up is 18.3 months. Median patient age was 61.7 years (range 36 – 77). Twenty-nine patients are evaluable for toxicity and response. There were 10 partial responses (33%), with the median duration of response being 8.3 months (range 2–18) and median time to progression of 5.3 mths. Response rates were lower (21%) and progression free survival shorter (3.9 mths) in patients that had received all standard chemotherapy options (n = 14). No responses were seen in patients with a poor performance status (n = 3) or extrahepatic disease (n = 6). Overall treatment related toxicity was acceptable, however significant late toxicity included 4 cases of gastric ulceration. CONCLUSION: In patients with metastatic colorectal cancer that have previously received treatment with 5-FU based chemotherapy, treatment with SIR-spheres has demonstrated encouraging activity. Further studies are required to better define the subsets of patients most likely to respond

Circulation first – the time has come to question the sequencing of care in the ABCs of trauma; an American Association for the Surgery of Trauma multicenter trial

Background The traditional sequence of trauma care: Airway, Breathing, Circulation (ABC) has been practiced for many years. It became the standard of care despite the lack of scientific evidence. We hypothesized that patients in hypovolemic shock would have comparable outcomes with initiation of bleeding treatment (transfusion) prior to intubation (CAB), compared to those patients treated with the traditional ABC sequence. Methods This study was sponsored by the American Association for the Surgery of Trauma multicenter trials committee. We performed a retrospective analysis of all patients that presented to trauma centers with presumptive hypovolemic shock indicated by pre-hospital or emergency department hypotension and need for intubation from January 1, 2014 to July 1, 2016. Data collected included demographics, timing of intubation, vital signs before and after intubation, timing of the blood transfusion initiation related to intubation, and outcomes. Results From 440 patients that met inclusion criteria, 245 (55.7%) received intravenous blood product resuscitation first (CAB), and 195 (44.3%) were intubated before any resuscitation was started (ABC). There was no difference in ISS, mechanism, or comorbidities. Those intubated prior to receiving transfusion had a lower GCS than those with transfusion initiation prior to intubation (ABC: 4, CAB:9, p = 0.005). Although mortality was high in both groups, there was no statistically significant difference (CAB 47% and ABC 50%). In multivariate analysis, initial SBP and initial GCS were the only independent predictors of death. Conclusion The current study highlights that many trauma centers are already initiating circulation first prior to intubation when treating hypovolemic shock (CAB), even in patients with a low GCS. This practice was not associated with an increased mortality. Further prospective investigation is warranted. Trial registration IRB approval number: HM20006627. Retrospective trial not registered