331 research outputs found
Implementation Guidance for Wood Harvesting and Storage
This implementation guidance focuses on carbon removal and sequestration via
wood harvesting and storage (WHS), a process where woody biomass, with the
embedded carbon, is stored for long timescales in shallow geologic storage. The
engineering structure designed to ensure such durable storage by preventing
biomass decomposition is called a Wood Vault.
This guidance contains the requirements for a basic Wood Vault project, and
is intended to aid project developers, verifiers, and registries in this space.
It describes a set of requirements that govern the end-to-end process of carbon
removal and sequestration. This includes carbon accounting, wood sourcing via
wood residual (WR) utilization, Wood Vault construction and maintenance, as
well as processes for monitoring, verification, and credit issuance. Carbon
accounting requirements include baseline, or counterfactual specification, and
full life cycle analysis (LCA) within a specified process boundary. For the
vault itself, the guidance describes a buried vault with the burial chamber
covered by a layer of low permeability material to create anoxic condition.
Other types of vaults can also be used to adjust to local environmental,
transport, and economic constraints. Monitoring and verification requirements
include in-situ sensors, gas sampling, sample excavations, and site
maintenance. This guidance also contemplates land ownership and legal
assurances, as well as environmental and societal impact assessments.
The implementation guidance concludes with recommendations regarding
auditing, certification and carbon credit issuance
Pyridoxamine lowers kidney crystals in experimental hyperoxaluria: A potential therapy for primary hyperoxaluria
Pyridoxamine lowers kidney crystals in experimental hyperoxaluria: A potential therapy for primary hyperoxaluria.BackgroundPrimary hyperoxaluria is a rare genetic disorder of glyoxylate metabolism that results in overproduction of oxalate. The disease is characterized by severe calcium oxalate nephrolithiasis and nephrocalcinosis, resulting in end-stage renal disease (ESRD) early in life. Most patients eventually require dialysis and kidney transplantation, usually in combination with the replacement of the liver. Reduction of urinary oxalate levels can efficiently decrease calcium oxalate depositions; yet, no treatment is available that targets oxalate biosynthesis. In previous in vitro studies, we demonstrated that pyridoxamine can trap reactive carbonyl compounds, including intermediates of oxalate biosynthesis.MethodsThe effect of PM on urinary oxalate excretion and kidney crystal formation was determined using the ethylene glycol rat model of hyperoxaluria. Animals were given 0.75% to 0.8% ethylene glycol in drinking water to establish and maintain hyperoxaluria. After 2 weeks, pyridoxamine treatment (180mg/day/kg body weight) started and continued for an additional 2 weeks. Urinary creatinine, glycolate, oxalate, and calcium were measured along with the microscopic analysis of kidney tissues for the presence of calcium oxalate crystals.ResultsPyridoxamine treatment resulted in significantly lower (by ∼50%) levels of urinary glycolate and oxalate excretion compared to untreated hyperoxaluric animals. This was accompanied by a significant reduction in calcium oxalate crystal formation in papillary and medullary areas of the kidney.ConclusionThese results, coupled with favorable toxicity profiles of pyridoxamine in humans, show promise for therapeutic use of pyridoxamine in primary hyperoxaluria and other kidney stone diseases
Combining silver- and organocatalysis: an enantioselective sequential catalytic approach towards pyrano-annulated pyrazoles
Genetic architecture of laterality defects revealed by whole exome sequencing
Aberrant left-right patterning in the developing human embryo can lead to a broad spectrum of congenital malformations. The causes of most laterality defects are not known, with variants in established genes accounting for <20% of cases. We sought to characterize the genetic spectrum of these conditions by performing whole-exome sequencing of 323 unrelated laterality cases. We investigated the role of rare, predicted-damaging variation in 1726 putative laterality candidate genes derived from model organisms, pathway analyses, and human phenotypes. We also evaluated the contribution of homo/hemizygous exon deletions and gene-based burden of rare variation. A total of 28 candidate variants (26 rare predicted-damaging variants and 2 hemizygous deletions) were identified, including variants in genes known to cause heterotaxy and primary ciliary dyskinesia (ACVR2B, NODAL, ZIC3, DNAI1, DNAH5, HYDIN, MMP21), and genes without a human phenotype association, but with prior evidence for a role in embryonic laterality or cardiac development. Sanger validation of the latter variants in probands and their parents revealed no de novo variants, but apparent transmitted heterozygous (ROCK2, ISL1, SMAD2), and hemizygous (RAI2, RIPPLY1) variant patterns. Collectively, these variants account for 7.1% of our study subjects. We also observe evidence for an excess burden of rare, predicted loss-of-function variation in PXDNL and BMS1- two genes relevant to the broader laterality phenotype. These findings highlight potential new genes in the development of laterality defects, and suggest extensive locus heterogeneity and complex genetic models in this class of birth defects
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
3D-CLEM reveals that a major portion of mitotic chromosomes is not Chromatin
Recent studies have revealed the importance of Ki-67 and the chromosome periphery in chromosome structure and segregation, but little is known about this elusive chromosome compartment. Here we used correlative light and serial block-face scanning electron microscopy, which we term 3D-CLEM, to model the entire mitotic chromosome complement at ultra-structural resolution. Prophase chromosomes exhibit a highly irregular surface appearance with a volume smaller than metaphase chromosomes. This may be because of the absence of the periphery, which associates with chromosomes only after nucleolar disassembly later in prophase. Indeed, the nucleolar volume almost entirely accounts for the extra volume found in metaphase chromosomes. Analysis of wild-type and Ki-67-depleted chromosomes reveals that the periphery comprises 30%-47% of the entire chromosome volume and more than 33% of the protein mass of isolated mitotic chromosomes determined by quantitative proteomics. Thus, chromatin makes up a surprisingly small percentage of the total mass of metaphase chromosomes
Pediatric Acupuncture: A Review of Clinical Research
Practiced in China for more than 2000 years, acupuncture has recently gained increased attention in the United States as an alternative treatment approach for a variety of medical conditions. Despite its growing prevalence and anecdotal reports of success among pediatric populations, few empirically based studies have assessed the efficacy of acupuncture for children and adolescents. This article presents a review of the current literature, including a systematic appraisal of the methodological value of each study and a discussion of potential benefits and adverse effects of acupuncture. While acupuncture holds great promise as a treatment modality for diverse pediatric conditions, a significant amount of additional research is necessary to establish an empirical basis for the incorporation of acupuncture into standard care
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