Increase in CFC-11 emissions from eastern China based on atmospheric observations.

The recovery of the stratospheric ozone layer relies on the continued decline in the atmospheric concentrations of ozone-depleting gases such as chlorofluorocarbons1. The atmospheric concentration of trichlorofluoromethane (CFC-11), the second-most abundant chlorofluorocarbon, has declined substantially since the mid-1990s2. A recently reported slowdown in the decline of the atmospheric concentration of CFC-11 after 2012, however, suggests that global emissions have increased3,4. A concurrent increase in CFC-11 emissions from eastern Asia contributes to the global emission increase, but the location and magnitude of this regional source are unknown3. Here, using high-frequency atmospheric observations from Gosan, South Korea, and Hateruma, Japan, together with global monitoring data and atmospheric chemical transport model simulations, we investigate regional CFC-11 emissions from eastern Asia. We show that emissions from eastern mainland China are 7.0 ± 3.0 (±1 standard deviation) gigagrams per year higher in 2014-2017 than in 2008-2012, and that the increase in emissions arises primarily around the northeastern provinces of Shandong and Hebei. This increase accounts for a substantial fraction (at least 40 to 60 per cent) of the global rise in CFC-11 emissions. We find no evidence for a significant increase in CFC-11 emissions from any other eastern Asian countries or other regions of the world where there are available data for the detection of regional emissions. The attribution of any remaining fraction of the global CFC-11 emission rise to other regions is limited by the sparsity of long-term measurements of sufficient frequency near potentially emissive regions. Several considerations suggest that the increase in CFC-11 emissions from eastern mainland China is likely to be the result of new production and use, which is inconsistent with the Montreal Protocol agreement to phase out global chlorofluorocarbon production by 2010.

Recent trends in global emissions of hydrochlorofluorocarbons and hydrofluorocarbons: reflecting on the 2007 adjustments to the Montreal Protocol.

Global-scale atmospheric measurements are used to investigate the effectiveness of recent adjustments to production and consumption controls on hydrochlorofluorocarbons (HCFCs) under the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) and to assess recent projections of large increases in hydrofluorocarbon (HFC) production and emission. The results show that aggregate global HCFC emissions did not increase appreciably during 2007-2012 and suggest that the 2007 Adjustments to the Montreal Protocol played a role in limiting HCFC emissions well in advance of the 2013 cap on global production. HCFC emissions varied between 27 and 29 kt CFC-11-equivalent (eq)/y or 0.76 and 0.79 GtCO2-eq/y during this period. Despite slower than projected increases in aggregate HCFC emissions since 2007, total emissions of HFCs used as substitutes for HCFCs and chlorofluorocarbons (CFCs) have not increased more rapidly than rates projected [Velders, G. J. M.; Fahey, D. W.; Daniel, J. S.; McFarland, M.; Andersen, S. O. The Large Contribution of Projected HFC Emissions to Future Climate Forcing. Proc. Natl. Acad. Sci. U.S.A. 2009, 106, 10949-10954] for 2007-2012. HFC global emission magnitudes related to this substitution totaled 0.51 (-0.03, +0.04) GtCO2-eq/y in 2012, a magnitude about two times larger than emissions reported to the United Nations Framework Convention on Climate Change (UNFCCC) for these HFCs. Assuming accurate reporting to the UNFCCC, the results imply that developing countries (non-Annex I Parties) not reporting to the UNFCCC now account for nearly 50% of global HFC emissions used as substitutes for ozone-depleting substances (ODSs). Global HFC emissions (as CO2-eq) from ODS substitution can be attributed approximately equally to mobile air conditioning, commercial refrigeration, and the sum of all other applications.

Ocular manifestations of branchio-oculo-facial syndrome: report of a novel mutation and review of the literature.

PURPOSE: To report unusual ocular manifestations of branchio-oculo-facial syndrome (BOFS) caused by a novel mutation in activating enhancer binding protein 2 alpha (TFAP2A). METHODS: Full ophthalmological evaluation and direct sequencing of TFAP2A. RESULTS: A 10-year-old girl with unusual ocular manifestations of BOFS such as elliptical shaped microcornea and a novel de novo TFAP2A mutation was identified. CONCLUSIONS: This report expands the ocular phenotypic spectrum of BOFS and adds to the small number of reported TFAP2A mutations.

Application of gas chromatography with a pulsed discharge helium ionization detector for measurements of molecular hydrogen in the atmosphere.

The Earth's troposphere contains approximately 160 Tg H2 with an average surface mixing ratio approximately 530 nmole mole(-1) (ppb) and lifetime of 2 years. Atmospheric H2 is typically measured using gas chromatography (GC) followed by hot mercuric oxide reduction detection (GC-HgO). Here we describe an alternate method using GC with a pulsed-discharge helium ionization detector (HePPD). HePPD is a universal detector; when applied to H2, the GC-HePDD provides a wide linear range (0.3% over a range of 2000 ppb), a detection limit of approximately 0.03 pg, high precision (0.12%) and a stable response (+/-1.6% over nearly one year). HePPD is compared to HgO reduction using a suite of gravimetrically prepared reference gases spanning remote to urban concentrations. The method is excellent for atmospheric measurements as it provides a wide linear range with high precision, stability and reproducibility. We suggest these characteristics will improve the ability to maintain reference gases and improve measurements of atmospheric H2, thus providing better constraints on potential future changes in its sources and sinks.

Wetlands as principal zones of methylmercury production in southern Louisiana and the Gulf of Mexico region.

It is widely recognized that wetlands, especially those rich in organic matter and receiving appreciable atmospheric mercury (Hg) inputs, are important sites of methylmercury (MeHg) production. Extensive wetlands in the southeastern United States have many ecosystem attributes ideal for promoting high MeHg production rates; however, relatively few mercury cycling studies have been conducted in these environments. We conducted a landscape scale study examining Hg cycling in coastal Louisiana (USA) including four field trips conducted between August 2003 and May 2005. Sites were chosen to represent different ecosystem types, including: a large shallow eutrophic estuarine lake (Lake Pontchartrain), three rivers draining into the lake, a cypress-tupelo dominated freshwater swamp, and six emergent marshes ranging from a freshwater marsh dominated by Panicum hemitomon to a Spartina alterniflora dominated salt marsh close to the Gulf of Mexico. We measured MeHg and total Hg (THg) concentrations, and ancillary chemical characteristics, in whole and filtered surface water, and filtered porewater. Overall, MeHg concentrations were greatest in surface water of freshwater wetlands and lowest in the profundal (non-vegetated) regions of the lake and river mainstems. Concentrations of THg and MeHg in filtered surface water were positively correlated with the highly reactive, aromatic (hydrophobic organic acid) fraction of dissolved organic carbon (DOC). These results suggest that DOC plays an important role in promoting the mobility, transport and bioavailability of inorganic Hg in these environments. Further, elevated porewater concentrations in marine and brackish wetlands suggest coastal wetlands along the Gulf Coast are key sites for MeHg production and may be a principal source of MeHg to foodwebs in the Gulf of Mexico. Examining the relationships among MeHg, THg, and DOC across these multiple landscape types is a first step in evaluating possible links between key zones for Hg(II)-methylation and the bioaccumulation of mercury in the biota inhabiting the Gulf of Mexico region.

Atmospheric mercury speciation in Yellowstone National Park.

Atmospheric concentrations of elemental mercury (Hg(0)), reactive gaseous Hg (RGM), and particulate Hg (pHg) concentrations were measured in Yellowstone National Park (YNP), U.S.A. using high resolution, real time atmospheric mercury analyzers (Tekran 2537A, 1130, and 1135). A survey of Hg(0) concentrations at various locations within YNP showed that concentrations generally reflect global background concentrations of 1.5-2.0 ng m(-3), but a few specific locations associated with concentrated geothermal activity showed distinctly elevated Hg(0) concentrations (about 9.0 ng m(-3)). At the site of intensive study located centrally in YNP (Canyon Village), Hg(0) concentrations did not exceed 2.5 ng m(-3); concentrations of RGM were generally below detection limits of 0.88 pg m(-3) and never exceeded 5 pg m(-3). Concentrations of pHg ranged from below detection limits to close to 30 pg m(-3). RGM and pHg concentrations were not correlated with any criteria gases (SO(2), NO(x), O(3)); however pHg was weakly correlated with the concentration of atmospheric particles. We investigated three likely sources of Hg at the intensive monitoring site: numerous geothermal features scattered throughout YNP, re-suspended soils, and wildfires near or in YNP. We examined relationships between the chemical properties of aerosols (as measured using real time, single particle mass spectrometry; aerosol time-of-flight mass spectrometer; ATOFMS) and concentrations of atmospheric pHg. Based on the presence of particles with distinct chemical signatures of the wildfires, and the absence of signatures associated with the other sources, we concluded that wildfires in the park were the main source of aerosols and associated pHg to our sampling site.

Importance of the forest canopy to fluxes of methyl mercury and total mercury to boreal ecosystems.

The forest canopy was an important contributor to fluxes of methyl mercury (MeHg) and total mercury (THg) to the forest floor of boreal uplands and wetlands and potentially to downstream lakes, at the Experimental Lakes Area (ELA), northwestern Ontario. The estimated fluxes of MeHg and THg in throughfall plus litterfall below the forest canopy were 2 and 3 times greater than annual fluxes by direct wet deposition of MeHg (0.9 mg of MeHg ha(-1)) and THg (71 mg of THg ha(-1)). Almost all of the increased flux of MeHg and THg under the forest canopy occurred as litterfall (0.14-1.3 mg of MeHg ha(-1) yr(-1) and 110-220 mg of THg ha(-1) yr(-1)). Throughfall added no MeHg and approximately 9 mg of THg ha(-1) yr(-1) to wet deposition at ELA, unlike in other regions of the world where atmospheric deposition was more heavily contaminated. These data suggest that dry deposition of Hg on foliage as an aerosol or reactive gaseous Hg (RGM) species is low at ELA, a finding supported by preliminary measurements of RGM there. Annual total deposition from throughfall and litterfall under a fire-regenerated 19-yr-old jack pine/birch forest was 1.7 mg of MeHg ha(-1) and 200 mg of THg ha(-1). We found that average annual accumulation of MeHg and THg in the surficial litter/fungal layer of soils since the last forest fire varied between 0.6 and 1.6 mg of MeHg ha(-1) and between 130 and 590 mg of THg ha(-1) among sites differing in drainage and soil moisture. When soil Hg accumulation sites were matched with similar sites where litterfall and throughfall were collected, measured fluxes of THg to the forest floor (sources) were similar to our estimates of longterm soil accumulation rates (sinks), suggesting that the Hg in litterfall and throughfall is a new and not a recycled input of Hg to forested ecosystems. However, further research is required to determine the proportion of Hg in litterfall that is being biogeochemically recycled within forest and wetland ecosystems and, thus, does not represent new inputs to the forest ecosystem.

The subtle facial signs of prenatal exposure to alcohol: an anthropometric approach.

OBJECTIVES: The purpose was to demonstrate that an objective, multivariate case definition of fetal alcohol syndrome (FAS) and partial fetal alcohol syndrome (PFAS) can be derived by means of craniofacial anthropometry. STUDY DESIGN: Craniofacial measurements (n = 21) were taken of 100 individuals who had been exposed to alcohol before birth (41 FAS, 59 PFAS) and 31 members of a control group. Multivariate discriminant analysis was used to identify craniofacial measurements that best differentiated the 3 groups (FAS, PFAS, and control). RESULTS: Both the FAS and PFAS groups had a unique craniofacial phenotype that could be accurately discriminated from that of the control group. Stepwise discriminant analysis identified 6 craniofacial measurements that could differentiate individuals with and without prenatal alcohol exposure with 96% accuracy, 98% sensitivity, and 90% specificity. CONCLUSIONS: Individuals with FAS and PFAS have a distinctive facial phenotype that can be characterized anthropometrically. The phenotypic case definition could be used as a screening tool to identify individuals prenatally exposed to alcohol who do not exhibit a "classic" FAS phenotype but exhibit a more subtle craniofacial dysmorphia.

Meier-Gorlin syndrome: report of eight additional cases and review.

The Meier-Gorlin syndrome or ear, patella, short stature syndrome (MIM 224690) is a rare autosomal recessive disorder, characterized by the association of bilateral microtia, aplasia/hypoplasia of the patellae, and severe pre- and postnatal growth retardation. Twenty-one cases have been reported in literature thus far. Here we report on eight patients from seven families and compare them with previously described cases. One of the present cases had previously undescribed genital anomalies. There is a difference in facial characteristics between patients reported in early infancy and those described at older age; follow-up of patients is needed to substantiate this changing facial phenotype. We recommend radiographic survey of the patellae in patients at older age to investigate the weight of absent or hypoplastic patellae in the diagnosis of the syndrome.

Are red algae plants? A critical evaluation of three key molecular data sets.

Whether red algae are related to green plants has been debated for over a century. Features present due to their shared photosynthetic habit have been interpreted as support for an evolutionary sisterhood of the two groups but, until very recently, characters endogenous to the host cell have provided no reliable indication of such a relationship. In this investigation, we examine three molecular data sets that have provided key evidence of a possible relationship between green plants and red algae. Analyses of an expanded alignment of DNA-dependent RNA polymerase II largest subunit sequences indicate that their support for independent origins of rhodophytes and chlorophytes is not the result of long-branch attraction, as has been proposed elsewhere. Differences in the pol II C-terminal domain, an essential component of plant mRNA transcription, also suggest different host cell ancestors for the two groups. In contrast, concatenated sequences of two groups of mitochondrial genes, those encoding subunits of NADH-dehydrogenase as well as cytochrome c oxidase subunits plus apocytochrome B, appear to cluster red algal and green plant sequences together because both groups have evolved relatively slowly and share a super-abundance of ancestral positions. Finally, analyses of elongation factor 2 sequences demonstrate a strong phylogenetic signal favoring a rhodophyte/chlorophyte sister relationship, but that signal is restricted to a contiguous segment comprising approximately half of the EF2 gene. These results argue for great caution in the interpretation of phylogenetic analyses of ancient evolutionary events but, in combination, indicate that there is no emerging consensus from molecular data supporting a sister relationship between red algae and green plants.

Holoprosencephaly due to mutations in ZIC2: alanine tract expansion mutations may be caused by parental somatic recombination.

We report on the prevalence of mutations in the zinc finger transcription factor gene, ZIC2, in a group of 509 unrelated individuals with isolated holoprosencephaly (HPE) and normal chromosomes. Overall, we encountered 16 HPE patients (from 15 unrelated families) with ZIC2 mutations. Thus, ZIC2 mutation was the apparent cause of HPE in 3-4% of cases. Seven mutations were frameshifts that were predicted to result in loss of function, further supporting the idea that ZIC2 haploinsufficiency can result in HPE. One mutation, an alanine tract expansion which is caused by the expansion of an imperfect trinucleotide repeat, occurred in seven patients from six different families. In three of those families, the father was found to be apparently mosaic for the mutation. We hypothesize that this mutation can arise through errors in somatic recombination, an extremely unusual mutation mechanism. In addition, one mutation resulted in a single amino acid change and one mutation was an in-frame deletion of 12 amino acids. The central nervous system malformations seen in patients with ZIC2 mutations ranged from alobar HPE (most common) to middle interhemispheric fusion defect (one case). Although severe facial anomalies are common in HPE, all of the patients with ZIC2 mutations had relatively normal faces, suggesting that ZIC2 mutations represent a large proportion of HPE cases without facial malformation.

Lethality in Desbuquois dysplasia: three new cases.

Three new cases of Desbuquois syndrome in two brothers and a sporadic male, all of whom died in early infancy, are presented to emphasize the high rate (33 %) of lethality in this variable, but serious skeletal dysplasia. Including the three presented patients and 10 of the 36 cases in the literature who died, most did so between birth and 7 months and from respiratory-related problems. Neonatal and infancy survivors should be monitored closely, particularly relative to their pulmonary status.

Spectrum of Schwartz-Jampel syndrome includes micromelic chondrodysplasia, kyphomelic dysplasia, and Burton disease.

Follow-up and re-evaluation of four patients originally described as examples of severe infantile "micromelic chondrodysplasia" resembling Kniest disease, "kyphomelic dysplasia," and "Burton skeletal dysplasia" revealed the diagnosis of Schwartz-Jampel syndrome (SJS, myotonic chondrodysplasia) in all of them. SJS may be suspected in neonates with Kniest-like chondrodysplasia, congenital bowing of shortened femora and tibiae, and facial manifestations consisting of a small mouth, micrognathia, and possibly pursed lips. The disorder must be differentiated from the Stüve-Wiedemann syndrome, a genetically distinct myotonic chondrodysplasia with similar clinical but different skeletal changes and an unfavorable early prognosis. The demise of "kyphomelic dysplasia" as a nosological entity reemphasizes the symptomatic nature of congenital bowing of the long bones.

Evolutionary complementation for polymerase II CTD function.

The C-terminal domain (CTD) of the largest subunit (RPB1) of eukaryotic RNA polymerase II is essential for pol II function and has been shown to play a number of important roles in the mRNA transcription cycle. The CTD is composed of a tandemly repeated heptapeptide that is conserved in yeast, animals, plants and several protistan organisms. Some eukaryotes, however, have what appear to be degenerate or deviant CTD regions, and others have no CTD at all. The functional and evolutionary implications of this variation among RPB1 C-termini is largely unexplored. We have transformed yeast cells with a construct consisting of the yeast RPB1 gene with 25 heptads from the primitive protist Mastigamoeba invertens in place of the wild-type CTD. The Mastigamoeba heptads differ from the canonical CTD by the invariable presence of alanines in place of threonines at position 4, and in place of serines at position 7 of each heptad. Despite this double substitution, mutants are viable even under conditions of temperature and nutrient stress. These results provide new insights into the relative functional importance of several of the conserved CTD residues, and indicate that in vivo expression of evolutionary variants in yeast can provide important clues for understanding the origin, evolution and function of the pol II CTD.

Neonatal progeroid (Wiedemann-Rautenstrauch) syndrome: report of five new cases and review.

The neonatal progeroid syndrome (NPS), or Wiedemann-Rautenstrauch, is a rare autosomal recessive disorder comprised of generalized lipoatrophy except for fat pads in the suprabuttock areas, hypotrichosis of the scalp hair, eyebrows, and eyelashes, relative macrocephaly, triangular face, natal teeth, and micrognathia. We report on 5 new patients who demonstrate phenotypic variability and who represent the single largest series of NPS reported to date. Two of the patients are from an African-American kindred, an ethnic occurrence not reported previously. The fact that there are 2 pairs of sibs among the 5 patients further supports that NPS is an autosomal recessive condition. This report also includes a review of the previously reported 16 patients and compares them with the 5 new patients. Abnormalities in endocrine and lipid metabolism were found in 3 of 5 patients. Skeletal findings in 2 of our patients demonstrated some new findings as well as the typical radiological abnormalities previously noted in NPS. It is apparent, based on the 21 cases, that mild to moderate mental retardation is common in NPS. Long term follow-up of patients with NPS should provide more information relative to their ultimate psychomotor development. NPS is usually lethal by 7 months; however, on rare occasions, patients have survived into the teens. Our 3 surviving patients range in age from 16-23 months. Variability in the phenotype of NPS is clear; however, the phenotype remains distinct enough to allow a secure diagnosis.

Phylogenetic relationships among ascomycetes: evidence from an RNA polymerse II subunit.

In an effort to establish a suitable alternative to the widely used 18S rRNA system for molecular systematics of fungi, we examined the nuclear gene RPB2, encoding the second largest subunit of RNA polymerase II. Because RPB2 is a single-copy gene of large size with a modest rate of evolutionary change, it provides good phylogenetic resolution of Ascomycota. While the RPB2 and 18S rDNA phylogenies were highly congruent, the RPB2 phylogeny did result in much higher bootstrap support for all the deeper branches within the orders and for several branches between orders of the Ascomycota. There are several strongly supported phylogenetic conclusions. The Ascomycota is composed of three major lineages: Archiascomycetes, Saccharomycetales, and Euascomycetes. Within the Euascomycetes, plectomycetes, and pyrenomycetes are monophyletic groups, and the Pleosporales and Dothideales are distinct sister groups within the Loculoascomycetes. We confirm the placement of Neolecta within the Archiascomycetes, suggesting that fruiting body formation and forcible discharge of ascospores were characters gained early in the evolution of the Ascomycota. These findings show that a slowly evolving protein-coding gene such as RPB2 is useful for diagnosing phylogenetic relationships among fungi.

Antisense suppression of tomato endo-1,4-beta-glucanase Cel2 mRNA accumulation increases the force required to break fruit abscission zones but does not affect fruit softening.

Plants of tomato (Lycopersicon esculentum Mill. cv. T5) were transformed with an antisense endo-1,4-beta-glucanase (cellulase, EC 3.2.1.4) Cel2 transgene under the control of the constitutive cauliflower mosaic virus 35S promoter in order to suppress mRNA accumulation of Cel2. In two independent transgenic lines, Cel2 mRNA abundance was reduced by >95% in ripe fruit pericarp and ca. 80% in fruit abscission zones relative to non-transgenic controls. In both transgenic lines the softening of antisense Cel2 fruit pericarp measured using stress-relaxation analysis was indistinguishable from control fruit. No differences in ethylene evolution were observed between fruit of control and antisense Cel2 genotypes. However, in fruit abscission zones the suppression of Cel2 mRNA accumulation caused a significant (P<0.001) increase in the force required to cause breakage of the abscission zone at 4 days post breaker, an increase of 27% in one transgenic line and of 46% in the other transgenic line. Thus the Cel2 gene product contributes to cell wall disassembly occurring in cell separation during fruit abscission, but its role, if any, in softening or textural changes occurring in fruit pericarp during ripening was not revealed by suppression of Cel2 gene expression.

Mutational analysis of the hydrolytic activity of yeast RNA polymerase III.

For 25 mutant alleles of ret1, encoding the second largest subunit of yeast RNA polymerase III, we have studied the polymerase III nuclease activity, measuring both the total yield and dinucleotide product composition. Mutations affecting amino acids 309-325 gave slightly elevated nuclease activity. In region 367-376, two mutations gave 12-15-fold increased nuclease activity. Our results do not support the catalytic role in nuclease activity proposed for the conserved DDRD motif in this region (Shirai, T., and Go, M. (1991) Proc. Natl. Acad. Sci. U. S. A. 88, 9056-9060). Mutations centered on a basic region from amino acids 480 to 490, which aligns with Escherichia coli beta-subunit sequences between Rif(r) clusters I and II, produce changes in the relative yields of A- and G-containing dinucleotides. Four such mutant polymerases pause during elongation at GPy sequences and, in addition, have a reduced frequency of termination at T(5) terminator sequences. We propose that the side chains of these mutationally altered amino acids are in direct contact with bases in the RNA-DNA hybrid very near the growing 3'-end. Two mutations in domain I near the C terminus produced very large increases in exonuclease activity and strongly increased termination, suggesting that this region also contacts the nascent RNA in the hybrid region.

Albinism and agenesis of the corpus callosum with profound developmental delay: Vici syndrome, evidence for autosomal recessive inheritance.

We report on two sibs and two other unrelated patients with agenesis of corpus callosum, oculocutaneous albinism, repeated infections, and cardiomyopathy. All manifested postnatal growth retardation, microcephaly, and profound developmental delay. Additional central nervous system anomalies present in at least one patient included hypoplasia of the cerebellar vermis, white matter neuronal heterotopia, or bilateral schizencephaly. Repeated viral, bacterial, and fungal infections were consistent with a primary immunodeficiency. However, immunological studies showed variable, nonspecific findings. Cardiomyopathy with progressive heart failure or infection led to death before age 2 years in three of the patients. This syndrome was first described by Vici et al. [1988: Am. J. Med. Genet. 29:1-8]. The four patients reported herein confirm this unique disorder. Affected sibs of both sexes born to unaffected parents provide evidence for autosomal recessive inheritance.

X-linked mental retardation with variable stature, head circumference, and testicular volume linked to Xq12-q21.

Clinical and molecular studies are reported on a family with X-linked mental retardation (XLMR) in which there are eight affected males in three generations. Although the males have somatic manifestations, these are variable and in most cases do not allow clear distinction of affected and unaffected males. Affected males are shorter and have a smaller head circumference. Several also have a sloping forehead (5/8), hearing loss (3/8), cupped ears (2/8), and small testes (4/6). An LOD score of 4.41 with zero recombination was obtained at locus DXS1166 in Xq13.2. This family highlights the difficulty in classifying XLMR conditions as either nonsyndromic or syndromic because of the variable somatic manifestations observed in the affected males.