Temporal patterns in the soundscape of a Norwegian gateway to the Arctic.

As an Arctic gateway, the Norwegian Sea sustains a rich diversity of seasonal and resident species of soniferous animals, vulnerable to the effects of climate change and anthropogenic activities. We show the occurrence of seasonal patterns of acoustic signals in a small canyon off Northern Norway, and investigate cetacean vocal behavior, human-made noise, and climatic contributions to underwater sound between January and May 2018. Mostly median sound levels ranged between 68.3 and 96.31 dB re 1 µPa2 across 1/3 octave bands (13 Hz-16 kHz), with peaks in February and March. Frequencies under 2 kHz were dominated by sounds from baleen whales with highest rates of occurrence during winter and early spring. During late-spring non-biological sounds were predominant at higher frequencies that were linked mainly to ship traffic. Seismic pulses were also recorded during spring. We observed a significant effect of wind speed and ship sailing time on received sound levels across multiple distance ranges. Our results provide a new assessment of high-latitude continental soundscapes in the East Atlantic Ocean, useful for management strategies in areas where anthropogenic pressure is increasing. Based on the current status of the local soundscape, we propose considerations for acoustic monitoring to be included in future management plans.

The DSmurf ubiquitin-protein ligase restricts BMP signaling spatially and temporally during Drosophila embryogenesis.

We identified Drosophila Smurf (DSmurf) as a negative regulator of signaling by the BMP2/4 ortholog DPP during embryonic dorsal-ventral patterning. DSmurf encodes a HECT domain ubiquitin-protein ligase, homologous to vertebrate Smurf1 and Smurf2, that binds the Smad1/5 ortholog MAD and likely promotes its proteolysis. The essential function of DSmurf is restricted to its action on the DPP pathway. DSmurf has two distinct, possibly mechanistically separate, functions in controlling DPP signaling. Prior to gastrulation, DSmurf mutations cause a spatial increase in the DPP gradient, as evidenced by ventrolateral expansion in expression domains of target genes representing all known signaling thresholds. After gastrulation, DSmurf mutations cause a temporal delay in downregulation of earlier DPP signals, resulting in a lethal defect in hindgut organogenesis.

Conservation of dorsal-ventral patterning in arthropods and chordates.

Dorsal-ventral patterning within the ectodermal and mesodermal germ layers of Drosophila and Xenopus embryos is specified by a system of genes that has been conserved over 500 million years of evolution. In both organisms, the activity of the TGF-beta family member DPP/BMP4 is antagonized by SOG/CHORDIN. A second Xenopus gene, noggin, has a similar biological activity to chordin. Analysis of the action of these genes indicate that Spemann's organizer promotes dorsal cell fates in Xenopus by antagonizing a ventralizing signal encoded by the Bmp4 gene.

Morphogen gradients: new insights from DPP.

The Drosophila TGFbeta family member Decapentaplegic (DPP) has been proposed to function as a morphogen to pattern cell fields in a number of developmental contexts. A series of recent reports add significantly to our knowledge of the mechanisms of DPP-gradient formation and interpretation. These reports identity additional genes and genetic circuitry necessary for this patterning system, and they highlight variations that might reflect developmental constraints within individual target cell fields.

Identification and characterization of 22 genes that affect the vulval cell lineages of the nematode Caenorhabditis elegans.

Ninety-five mutants of the nematode Caenorhabditis elegans altered in the cell lineages of the vulva have been isolated on the basis of their displaying one of two phenotypes, Vulvaless or Multivulva. In Vulvaless mutants, which define 12 genes, no vulva is present. In Multivulva mutants, which define ten genes, one or more supernumerary vulva-like protrusions are located along the ventral side of the animal. A single recessive mutation is responsible for the phenotypes of most, but not all, of these strains. Fifteen of these 22 genes are represented by multiple alleles. We have shown by a variety of genetic criteria that mutations that result in a Vulvaless or Multivulva phenotype in six of the 22 genes most likely eliminate gene function. In addition, Vulvaless or Multivulva mutations in seven of the other genes most likely result in a partial reduction of gene function; the absence of the activity of any of these genes probably results in lethality or sterility. Our results suggest that we may have identified most, or all, genes of these two classes.

The multivulva phenotype of certain Caenorhabditis elegans mutants results from defects in two functionally redundant pathways.

We previously identified Caenorhabditis elegans mutants in which certain of the six vulval precursor cells adopt fates normally expressed by other vulval precursor cells. These mutants define genes that appear to function in the response to an intercellular signal that induces vulval development. The multivulva (Muv) phenotype of one such mutant, CB1322, results from an interaction between two unlinked mutations, lin-8(n111) II and lin-9(n112) III. In this paper, we identify 18 new mutations, which are alleles of eight genes, that interact with either lin-8(n111) or lin-9(n112) to generate a Muv phenotype. None of these 20 mutations alone causes any vulval cell lineage defects. The "silent Muv" mutations fall into two classes; hermaphrodites carrying a mutation of each class are Muv, while hermaphrodites carrying two mutations of the same class have a wild-type vulval phenotype. Our results indicate that the Muv phenotype of these mutants results from defects in two functionally-redundant pathways, thereby demonstrating that redundancy can occur at the level of gene pathways as well as at the level of gene families.

Identification and characterization of genes that interact with lin-12 in Caenorhabditis elegans.

We identified and characterized 14 extragenic mutations that suppressed the dominant egg-laying defect of certain lin-12 gain-of-function mutations. These suppressors defined seven genes: sup-17, lag-2, sel-4, sel-5, sel-6, sel-7 and sel-8. Mutations in six of the genes are recessive suppressors, whereas the two mutations that define the seventh gene, lag-2, are semi-dominant suppressors. These suppressor mutations were able to suppress other lin-12 gain-of-function mutations. The suppressor mutations arose at a very low frequency per gene, 10-50 times below the typical loss-of-function mutation frequency. The suppressor mutations in sup-17 and lag-2 were shown to be rare non-null alleles, and we present evidence that null mutations in these two genes cause lethality. Temperature-shift studies for two suppressor genes, sup-17 and lag-2, suggest that both genes act at approximately the same time as lin-12 in specifying a cell fate. Suppressor alleles of six of these genes enhanced a temperature-sensitive loss-of-function allele of glp-1, a gene related to lin-12 in structure and function. Our analysis of these suppressors suggests that the majority of these genes are part of a shared lin-12/glp-1 signal transduction pathway, or act to regulate the expression or stability of lin-12 and glp-1.

Assessment of dietary zinc in a population.

Assessment of dietary zinc status in a population requires several steps, consisting of the measurement of food intake distributions in the population; the analysis of local staple foods, from which zinc intake distributions can be determined, and the comparison of zinc intakes with requirement estimates to determine the risk of inadequate intakes. In low-income countries, these steps may be complicated by the lack of preexisting food-composition data, variations in food preparation methods, inhibition of absorption by other compounds in the diet, and variations in intake among seasons, individuals, and populations. Different techniques for determining the adequacy of zinc intake are compared. Whereas the techniques described in this paper allow for the determination of probability estimates for risk of zinc inadequacy, they do not allow for the identification of actual individuals in a population who are zinc deficient, or define the severity of zinc inadequacy. This information is vital, especially in areas where zinc deficiency is but one of many health problems, and can be obtained only from more detailed biochemical and physiologic studies of zinc status.

Dietary calcium, phytate, and zinc intakes and the calcium, phytate, and zinc molar ratios of the diets of a selected group of East African children.

Dietary zinc, calcium, and phytate intakes of 66 rural Malawian children aged 4-6 y were determined during three seasons on the basis of weighed food records and analyzed food composition data. Height and weight measurements were also recorded and hair samples were collected for zinc analysis. Seasonal daily zinc, calcium, and phytate intakes of females ranged from 6.2 +/- 1.7 to 6.8 +/- 2.1 mg (mean +/- SD), from 335 +/- 170 to 401 +/- 257 mg, and from 1621 +/- 660 to 1729 +/- 592 mg, respectively and, for males, 7.0 +/- 1.7 to 8.0 +/- 2.3 mg, 342 +/- 164 to 473 +/- 310 mg, and 1857 +/- 530 to 2161 +/- 684 mg, respectively. Cereals provided greater than 42% of dietary zinc. Seasonal mean molar ratios of phytate to Zn and Ca x phytate to Zn [per 1000 kcal (4.2 MJ)] and the median Ca to phytate molar ratio ranged from 24 to 27, 151 to 188 mmol/1000 kcal (4.2 MJ), and 3.1 to 3.4, respectively. Over 78% of the children consumed diets with phytate-to-Zn and Ca x phytate.Zn-1 . 1000 kcal-1 molar ratios above values suggested to jeopardize zinc status. Correlations between hair zinc, phytate-to-Zn, and Ca x phytate.Zn-1 . 1000 kcal-1 molar ratios suggest that high phytic acid intakes may compromise zinc status in these children.

Complementary foods for infant feeding in developing countries: their nutrient adequacy and improvement.

OBJECTIVE: To assess the energy and nutrient adequacy of a variety of complementary foods used in parts of Africa, India, Papua New Guinea, the Philippines and Thailand. METHOD: The energy, nutrient and anti-nutrient (dietary fibre and phytic acid) content (per 100 g as eaten, per 100 kcal, and per day) of twenty-three plant-based complementary foods consumed in developing countries was calculated from food composition values based on chemical analysis for the trace minerals, non-starch polysaccharide and phytic acid, and the literature. Results were compared with the estimated nutrient needs (per day; per 100 kcal) from complementary foods for infants 9-11 months, assuming a breast milk intake of average volume and composition and three complementary feedings per day, each of 250 g. RESULTS: Complementary foods should provide approximately 25-50% of total daily requirements for protein, riboflavin and copper; 50-75% for thiamin, calcium and manganese; and 75-100% for phosphorus, zinc and iron. Most or all appear to meet the estimated daily nutrient needs (per day; per 100 kcal) from complementary foods for protein, thiamin and copper (per day), but not for calcium, iron, and in some cases zinc, even if moderate bioavailability for iron and zinc is assumed. Some of those based on rice are also inadequate in riboflavin (per day; per 100 kcal). CONCLUSIONS: Even if strategies to improve the bioavailability of iron and zinc are employed, they are probably insufficient to overcome the deficits in calcium, iron and zinc. Therefore, research on the feasibility of fortifying plant-based complementary foods in developing countries with calcium, iron and zinc is urgently required.

PIP: At about age 6 months, the supply of energy and some nutrients from breast milk no longer fully meets an infant's nutritional needs. Complementary foods must therefore be provided. In many developing countries, cereals or starchy roots and tubers are used as a basis for such additional foods. Findings are presented from a study conducted to assess the energy and nutrient adequacy of a variety of complementary foods used in parts of Africa, India, Papua New Guinea, the Philippines, and Thailand. The energy, nutrient, and anti-nutrient content of 23 plant-based complementary foods consumed in developing countries was calculated from food composition values based upon chemical analysis for trace minerals, non-starch polysaccharide and phytic acid, and the literature. Results were compared with the estimated nutrient needs from complementary foods for infants aged 9-11 months, assuming a breast milk intake of average volume and composition and 3 complementary feedings per day, each of 250 g. Complementary foods should provide approximately 25-50% of total daily requirements for protein, riboflavin, and copper; 50-75% for thiamin, calcium, and manganese; and 75-100% for phosphorous, zinc, and iron. While most or all of the foods appear to meet the estimated daily nutrient requirements of complementary foods for protein, thiamin, and copper, they do not for calcium, iron, and, in some cases, zinc, even if moderate bioavailability for iron and zinc is assumed. Some of the foods based upon rice are also inadequate in riboflavin.

The relative validity of the repeated 24 h recall for estimating energy and selected nutrient intakes of rural Ghanaian children.

OBJECTIVES: To investigate the relative validity of the 24 h recall for rural southern Ghanaian children. DESIGN: Cross-sectional study, in which food consumption was estimated for the same two days, using the recall and weighed record dietary techniques. SETTING: Two villages in the Greater Accra Region of Ghana. SUBJECTS: 72 rural children (39 females and 33 males; 56.2 +/- 9.4 months). RESULTS: Overall agreement in the number of foods reported was noted for 42% of records; 53% of recalls under-reported and 5% over-reported the number of foods consumed. Over 65% of snacks compared to less than 6% of main meal foods were missed on recalls. Average recalled portions were similar to weighed with the exception of cereal staples; for Slepor 250 g vs 295 g, P = 0.007 and for Gidantuba 272 g vs 260 g, P = 0.02. Average daily recalled intakes of energy and most nutrients were lower (P < or = 0.05) than weighted intakes in Slepor, but similar in Gidantuba. In both villages, the recalled and weighted nutrient intakes per MJ, and percentage energy from food groups, were similar. Intraclass correlations between recalled and weighed intakes ranged from 0.06 (energy) to 0.78 (vitamin A) per day, and per MJ from 0.36 to 0.76 for Fe in Gidantuba and Slepor, respectively. Less than 35% of recalled energy and nutrient intakes were within +/- 10% of weighed intakes. CONCLUSIONS: The recall could be substituted for the weighted record to estimate average intakes of energy and most nutrients, dietary quality and food consumption patterns, provided the average recalled serving of cereal staples was accurately estimated. For assessment of individual intakes or snack consumption, however, the recall technique was invalid. SPONSORSHIP: The International Development Research Centre and Natural Sciences and Engineering Research Council of Canada.

Iron deficiency and risk factors for lower iron stores in 6-24-month-old New Zealanders.

OBJECTIVES: To determine the prevalence of biochemical iron deficiency and identify factors associated with ferritin levels among 6-24-month-old urban South Island New Zealand children. DESIGN: Cross-sectional survey conducted from May 1998 to March 1999. SETTING: The cities of Christchurch, Dunedin and Invercargill. SUBJECTS: A total of 323 randomly selected 6-24-month-old children participated (response rate 61%) of which 263 provided a blood sample. METHODS: A complete blood cell count, zinc protoporphyrin, serum ferritin and C-reactive protein were measured on nonfasting venipuncture blood samples, 3-day weighed food records and general questionnaire data were collected. RESULTS: Among children with C-reactive protein<10 mg/l (n=231), 4.3% had iron deficiency anaemia, 5.6% had iron deficiency without anaemia, and 18.6% had depleted iron stores, when a ferritin cutoff of < or =12 g/l was used. Age (negative), sex (girls>boys), ethnicity (Caucasian>non-Caucasian), weight-for-age percentiles (negative) and birth weight (positive) were associated with ferritin after adjusting for infection and socioeconomic status. When current consumption of iron fortified formula and >500 ml of cows' milk per day were included, these were associated with a 22% increase and 25% decrease in ferritin, respectively (R2=0.28). CONCLUSIONS: The presence of suboptimal iron status (29%) among young New Zealand children is cause for concern, even though severe iron deficiency is rare, because children with marginal iron status are at risk of developing severe iron deficiency if exposed to a physiological challenge.

An interactive 24-h recall technique for assessing the adequacy of trace mineral intakes of rural Malawian women; its advantages and limitations.

OBJECTIVES: To assess the relative validity of an interactive 24-h recall for estimating mineral intakes of rural Malawian women. DESIGN: Repeated interactive 24-h recalls were compared with weighed records collected for the same 2 days of food intake, and for 2 days 1-2 weeks prior and subsequent to the weighed record data collection period. SETTING: Three villages in traditional authority Jalasi, Mangochi District, Malawi. SUBJECTS: 60 rural pregnant women. RESULTS: Median daily intakes of most minerals (Ca, Fe, Zn, Mn) were comparable for the two methods, but slightly overestimated for recalled (R) intakes expressed per MJ (mg/MJ) compared to weighed (W) (R vs W = Ca, 48 vs 38; Fe, 2.1 vs 1.9; Zn, 0.9 vs 0.8; Mn, 0.40 vs 0.38; P < or = 0.05). By contrast, recalled median daily intakes of energy (kJ), protein (g) fat (g) and Cu (mg) were slightly underestimated (R vs W = 6588 vs 7824; 51 vs 57; 14 vs 15; 1.3 vs 1.6, respectively; P < or = 0.05). Discrepancies were attributed primarily to inaccurate estimates of main meal food portions [R vs W = nsima (the main meal cereal style) 475 vs 557; and legume relish 171 vs 118 P < or = 0.001]. For classifying intakes into tertiles, agreement between the two methods was poor for daily intakes (Cohen's kappa < 0.40), but fair when expressed per MJ, and as a percentage of energy from food groups (Cohen's kappa > or = 0.40). Variance ratios for recall data were higher than corresponding ratios for the weighed intakes (R vs W = for energy, 4.87 vs 0.87), indicating poorer recall measurement precision. CONCLUSION: Results emphasise the importance of selecting the dietary method according to the study objectives, and the nutrients required.

Dietary iron intakes and biochemical iron status of 15-49 year old women in New Zealand: is there a cause for concern?

AIM: To assess dietary iron intakes and biochemical iron status of a nationally representative sample of nonpregnant 15-49 year old women (n=1,751) in New Zealand. METHODS: A cross-sectional national survey was conducted in 1996/97. Women were selected via a multistage stratified cluster sampling procedure with increased sampling of Maori and Pacific women. Dietary iron intakes were estimated using a 24-hour diet recall. Biochemical iron status was assessed on a non-fasting venipuncture blood sample (n=1,047) via haemoglobin, mean cell volume, erythrocyte zinc protoporphyrin, transferrin receptors and serum ferritin. RESULTS: Average daily dietary iron intakes ranged from 9.6 mg/day among Pacific women to 10.5 mg/day among Maori women; 41% of 20-49 year olds and 45% of adolescents were at risk of low dietary iron intakes. The estimated percentage of 15-49 year old women with iron deficiency anaemia ranged from 1.4-5.5%, and for iron deficiency without anaemia from 0.7-12.6% depending on the age group and criteria used. CONCLUSIONS: The overall estimated prevalence of suboptimal biochemical iron status among 15-49 year old women in New Zealand ranged from 7-13%, which compared favourably with premenopausal women living in other western countries. This situation is, however, a public health concern given the potential negative functional consequences associated with even mild iron deficiency.

Cognitive style and perception: the relationship between category width and speech perception, categorization, and discrimination.

Category width, as defined by Pettigrew's (1958) Category Width Scale, is a cognitive variable that purportedly reveals individual differences in categorization strategy. Subjects differ in terms of broadness and narrowness of judgments of category width--to what extent they will accept exemplars as good instances of a category. We tested the hypothesis that category width would be related to how subjects behave in different speech perception tasks. Differences found between extremely broad and narrow categorizers on such tasks would be helpful in understanding the nature of the perceptual and cognitive processes underlying the category width distinction. No effects attributable to category width were found when results were analyzed in terms of subjects' (a) discrimination and feature evaluation of auditory and visual information in speech events, (b) integration of these sources of information, (c) the process of decision, and (d) subjective preference for a two-choice versus a nine-choice response method. The results from both male and female and broad and narrow categorizers supported the predictions made by a fuzzy logical model of perception (FLMP). In the FLMP, people have access to continuous information about each feature of a stimulus, they make independent evaluations of each feature based on this information, the various features are integrated, and a decision is made based on the relative support for the viable alternatives. Given the common processes involved in speech and other pattern perceptual-recognition tasks, we conclude that fundamental processes involved in pattern recognition are unlikely to vary with personality measures, such as category width.

Do young New Zealand Pacific Island and European children differ in bone size or bone mineral?

Although Pacific Island adults have been shown to have larger bones and greater bone mineral density than caucasians, no previous studies have been undertaken to determine whether differences are present in prepubertal children. Forty-one Pacific Island children (both parents of Pacific Island descent) and 38 European children, aged 3 to 7 years, living in New Zealand were studied. Heights and weights were determined by simple anthropometry and body mass index (BMI, kg/m2) was calculated. Body composition, bone size, and bone mineral content (BMC, g) were measured by dual energy X-ray absorptiometry (DXA) of the total body and the non-dominant forearm. Compared to European children, in data adjusted for age and gender, Pacific Island children had significantly greater (P < 0.05) BMC in the total body (12%), the ultradistal radius (16%), and the 33% radius (8%), and also greater total body bone area (10%). Bone mineral density (BMD, g/cm2) was higher only at the ultradistal radius (11%). However, after adjustment for body weight, in particular lean mass, no differences were seen between Pacific Island and European children in any bone measure. The larger bone area and BMC of young Pacific Island children can be explained by their greater height and weight. Therefore, this study has shown that prepubertal Pacific Island children do not have greater bone size or BMC for their weight.

Fish are like flies are like frogs: conservation of dorsal-ventral patterning mechanisms.

Genetic analysis of Drosophila has shown that a morphogenetic gradient of the Transforming Growth Factor-beta family member dpp patterns the embryonic dorsal-ventral axis. Molecular and embryological evidence from Xenopus has strongly suggested a similar role for Bmp-4, the dpp homolog, in patterning the dorsal-ventral axis of chordates. A recent report has now identified mutations in two genes, dino and swirl, that disrupt dorsal-ventral patterning in the zebrafish Danio rerio. Characterization of these mutations parallels findings from Drosophila, thus establishing a genetic framework for the analysis of dorsal-ventral patterning in a vertebrate.

Decapentaplegic acts as a morphogen to organize dorsal-ventral pattern in the Drosophila embryo.

Zygotic expression of the Drosophila TGF beta family member decapentaplegic (dpp) is required for the development of the dorsal embryonic structures. By injecting dpp transcripts into young embryos, we find that 2- to 4-fold increases in the concentration of injected RNA elicit progressively more dorsal cell fates: only low levels of dpp permit development of ventral ectoderm, intermediate dpp levels drive dorsal epidermal development, and high dpp levels drive cells to differentiate as the most dorsal pattern element, the amnioserosa. Localized dpp RNA injections into embryos that lack all known maternal and zygotic dorsal-ventral polarity indicate that dpp can both define embryonic polarity and organize detailed patterning within the ectoderm. We infer that dpp acts as an extracellular morphogen and that the graded activity of dpp specifies the pattern of ectodermal cell fates in the Drosophila embryo.

Localized enhancement and repression of the activity of the TGF-beta family member, decapentaplegic, is necessary for dorsal-ventral pattern formation in the Drosophila embryo.

Seven zygotically active genes are required for normal patterning of the dorsal 40% of the Drosophila embryo. Among these genes, decapentaplegic (dpp) has the strongest mutant phenotype: in the absence of dpp, all cells in the dorsal and dorsolateral regions of the embryo adopt fates characteristic of more ventrally derived cells (Irish and Gelbart (1987) Genes Dev. 1, 868-879). Here we describe the phenotypes caused by alleles of another of this set of genes, tolloid, and show that tolloid is required for dorsal, but not dorsolateral, pattern. Extragenic suppressors of tolloid mutations were isolated that proved to be mutations that elevate dpp activity. We studied the relationship between tolloid and dpp by analyzing the phenotypes of tolloid embryos with elevated numbers of the dpp gene and found that doubling the dpp+ gene dosage completely suppressed weak tolloid mutants and partially suppressed the phenotypes of tolloid null mutants. We conclude that the function of tolloid is to increase dpp activity. We also examined the effect of doubling dpp+ gene dosage on the phenotypes caused by other mutations affecting dorsal development. Like tolloid, the phenotypes of mutant embryos lacking shrew gene function were suppressed by elevated dpp, indicating that shrew also acts upstream of dpp to increase dpp activity. In contrast, increasing the number of copies of the dpp gene enhanced the short gastrulation (sog) mutant phenotype, causing ventrolateral cells to adopt dorsal fates. This indicates that sog gene product normally blocks dpp activity ventrally. We propose that the tolloid, shrew and sog genes are required to generate a gradient of dpp activity, which directly specifies the pattern of the dorsal 40% of the embryo.