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Toothcombs have evolved independently in various mammalian lineages, including primates, scandentians and dermopterans, but the presence of a six-toothed toothcomb composed of four lower incisors and two canines (I1, I2 and C1, bilaterally) is a distinctive feature of extant strepsirrhine primates (Yamashita, 2017). There is some variation within the group with respect to the nature of the anterior teeth: indriids have a reduced toothcomb as a result of losing the lower canines (Gingerich, 1977), whereas Daubentonia has only one enlarged, ever-growing incisor, and no canines, in each quadrant (Quinn and Wilson, 2004). Nonetheless, it seems clear that a six-toothed toothcomb is primitive for Strepsirrhini (Hill, 1953b; Martin, 1990; Szalay and Delson, 1979). The earliest fossil strepsirrhine that indisputably possesses a toothcomb is Karanisia clarki (Seiffert et al., 2003), therefore the appearance of this trait can be established by as late as 36.9 million years ago (Mya). Molecular dates for the divergence of crown Strepsirrhini are generally much earlier than this (49.8–77.0 Mya; Pozzi et al., 2014b; Yang and Yoder, 2003, and sources cited therein). If the toothcomb was present in the common ancestor of the group, it could therefore be expected to have appeared much earlier than its first record in K. clarki. However, the fossil record for crown strepsirrhines remains very limited, which means that K. clarki provides the first window into the adaptive context in which the toothcomb evolved.
The first primate-like mammals to appear in the fossil record date to the earliest Palaeocene (Clemens, 2004; Fox and Scott, 2011; Silcox and López-Torres, 2017; Van Valen and Sloan, 1965), and the first primates of modern aspect (euprimates) do not appear until the latest Palaeocene/earliest Eocene (Morse et al., 2019; Ni et al., 2013; Rose et al., 2012; Sigé et al., 1990; Silcox et al., 2017; Smith et al., 2006). However, the most recent molecular estimates for the last common ancestor (LCA) of all living primates suggest that the order originated at some point between the late Cretaceous and the early Palaeocene (approximately between 60 and 70 Mya; Andrews et al., 2016; Herrera and Dávalos, 2016; Seiffert et al., 2018). Later, between 42 and 55 Mya (according to the same sources for molecular dates), Strepsirrhini split into the progenitors of the infraorders Lemuriformes and Lorisiformes (throughout this chapter we use the taxonomy established by Grubb et al., 2003). The Lemuriformes went on to radiate into the vast array of morphologically diverse living and extinct lemurs located on the island of Madagascar, and the lorisiforms split into two families: Lorisidae (pottos, angwantibos, slender lorises and slow lorises) and Galagidae, the bushbabies (Covert, 2002; Martin, 1990; Rasmussen and Nekaris, 1998).
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
There is an increasing incidence of overweight/obesity and mental health disorders in young adults and the two conditions often coexist. We aimed to investigate the influence of antenatal and postnatal factors that may underlie this association with a focus on maternal prenatal smoking, socio-economic status and gender. Data from the Western Australian Pregnancy Cohort (Raine) Study (women enrolled 1989–1991) including 1056 offspring aged 20 years (cohort recalled 2010–2012) were analyzed (2015–2016) using multivariable models for associations between offspring depression scores (DASS-21 Depression-scale) and body mass index (BMI), adjusting for pregnancy and early life factors and offspring behaviours. There was a significant positive relationship between offspring depression-score and BMI independent of gender and other psychosocial covariates. There was a significant interaction between maternal prenatal smoking and depression-score (interaction coefficient=0.096; 95% CI: 0.006, 0.19, P=0.037), indicating the relationship between depression-score and BMI differed according to maternal prenatal smoking status. In offspring of maternal prenatal smokers, a positive association between BMI and depression-score (coefficient=0.133; 95% CI: 0.05, 0.21, P=0.001) equated to 1.1 kg/m2 increase in BMI for every 1standard deviation (8 units) increase in depression-score. Substituting low family income during pregnancy for maternal prenatal smoking in the interaction (interaction coefficient=0.091; 95% CI: 0.01, 0.17, P=0.027) showed a positive association between BMI and depression score only among offspring of mothers with a low family income during pregnancy (coefficient=0.118; 95% CI: 0.06, 0.18, P<0.001). There were no significant effects of gender on these associations. Whilst further studies are needed to determine whether these associations are supported in other populations, they suggest potentially important maternal behavioural and socio-economic factors that identify individuals vulnerable to the coexistence of obesity and depression in early adulthood.
To report the introduction and impact of non-medical prescribing, initiated to improve patient pathways for those presenting with dizziness and balance disorders.
The Southport and Ormskirk physiotherapy-led vestibular clinic sees and treats all patients with dizziness and balance disorders referred to the ENT department. Letters are triaged by an audiologist, who also performs an otological examination and hearing test; this is followed by an assessment with the independent prescriber physiotherapist. An ENT consultant is nearby if joint consultation is needed. Diagnoses, treatments and patient satisfaction were studied, with an analysis of the impact of medication management (stopping or starting medicines) on patients and service.
In 12 months, 413 new patients with dizziness and balance disorders had appointments. The most common diagnoses were benign paroxysmal positional vertigo and vestibular migraine. Eighty-four per cent of patients required self-management strategies, 50 per cent exercise therapy, 48 per cent medication management and 24 per cent a particle repositioning manoeuvre. Patient satisfaction was high (99 per cent).
Having an independent prescriber physiotherapist leading the balance clinic has reduced the number of hospital visits and onward referrals. Nearly half of all patients required medication management as part of their dizziness or balance treatment.
Lysosomes are membrane bound cellular organelles that contain multiple hydrolases needed for the digestion of various macromolecules including mucopolysaccharides, glycosphingolipids and oligosaccharides. The lysosomal storage diseases are a group of over 40 diseases that are characterized by defective lysosomal function, leading to an accumulation of specific substrates within the lysosomes and eventual impairment of cellular function. A schematic of the lysosomal system enzyme trafficking and substrate accumulation is shown in Figure 32.1.
These diseases are classified by the nature of the stored material that results from the defects in selected lysosomal enzymes, their cofactors, and/or enzyme or substrate transport (Table 32.1). The lysosomal storage diseases are heterogeneous, progressive, multisystem diseases that have a spectrum of ages of onset, severity, rate of progression, and organ involvement. Lysosomal storage diseases have significant morbidity and mortality in the absence of effective treatment. The majority of these diseases are autosomal recessive and, although individually rare, the combined birth prevalence is approximately 1 in 7 000 live births . The diseases are traditionally diagnosed biochemically, but in many cases may also be confirmed molecularly by the identification of pathogenic mutations in one or both copies (X-linked conditions or autosomal recessive, respectively) of the specific genes.
Competition plays an important role in invasion dynamics. According to Elton's biodiversity and invasibility hypothesis, non-native species must be competitively superior to the resident species in order to successfully invade. An invader that is ecologically similar to a native species may cause intense interspecific competition as they both require the same resource. Furthermore, an increase in the density of an invading competitor may enhance the intensity of the competitive interaction, however, this may be reduced if the inferior competitor has a refuge that reduces the amount of time it is in direct contact with the superior competitor. In laboratory-based competition experiments between the non-native caprellid Caprella mutica and two ecologically similar native caprellids Caprella linearis and Pseudoprotella phasma, C. mutica successfully displaced both species from homogeneous artificial habitat patches after 48 hours. Patches that contained a refuge reduced the number of C. linearis being displaced but only when C. mutica was at a low density. Potentially aggressive interactions between C. mutica and the native C. linearis may have caused C. linearis to be displaced from the patches and could have caused significantly higher mortality of C. linearis compared to the controls. This is the first study to show that the non-native C. mutica has the ability to displace ecologically similar native species when the resource space is limited and when the density of C. mutica was significantly (10 times) lower than the density of C. linearis.
Single and multi-jet liquid impingers and membrane-filters were found to be efficient sampling devices for aerosols generated from suspensions of the virus of foot-and-mouth disease (FMD). Concentration of the aerosol samples with an adsorbent, Attaclay, facilitated the detection of small amounts of virus. Sodium dodecyl sulphate could be used for elution as the virus of FMD is resistant to this anionic detergent.
The penetration of these aerosols through various air filtration media was determined using impinger samplers. A glass fibre paper was found to be the most efficient with a virus penetration of less than 0·001%.
We wish to thank Dr D. W. Henderson and Dr H. M. Darlow, of M.R.E. and Mr R. G. Dorman of C.D.E. Porton for valuable prefatory discussions and advice. We are also indebted to Miss S. Cartwright for inoculating mice, to Miss M. Shoobridge and Mr S. Taylor for technical assistance, and to Vokes Ltd. for supplying materials.
T. Andrew Burrow, Resident, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio; Resident, Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio,
Kevin E. Bove, Professor of Pathology and Pediatrics, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio; Pediatric Pathologist, Division of Pathology and Laboratory Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio,
Gregory A. Grabowski, Professor, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio; Director, Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
Lysosomes are membrane-bound cellular organelles that contain multiple hydrolases needed for the digestion of various macromolecules, including mucopolysaccharides, glycosphingolipids, and oligosaccharides . The lysosomal storage diseases are a group of more than 40 diseases that are characterized by defective lysosomal function leading to an accumulation of specific substrates within the lysosomes and eventual impairment of cellular function. A schematic of the lysosomal system, enzyme trafficking, and substrate accumulation is shown in Figure 30.1.
These diseases are classified by the nature of the stored material that results from defects in selected lysosomal enzymes, their cofactors, and/or enzyme or substrate transport (Table 30.1). The lysosomal storage diseases are heterogeneous, progressive, multisystemic diseases that have a spectrum of ages of onset, severity, rates of progression, and organ involvement. Lysosomal storage diseases have significant morbidity and mortality in the absence of effective treatment. The majority of these diseases are autosomal recessive, and although individually each is rare, the combined birth prevalence is approximately 1 in 7000 live births . The diseases are traditionally diagnosed biochemically but in many cases, may also be diagnosed molecularly by the discovery of pathogenic mutations in both copies of the particular gene.
The liver is nearly always involved in lysosomal storage diseases; this can be seen at the light or electron microscopic level. The degree of clinical involvement depends on the disorder. In many cases, mild elevations in liver studies and hepatomegaly are the only manifestations. However, significant hepatic injury may be present, resulting in considerable morbidity.
This paper reports the first study of breeding in the boreo-arctic barnacle Semibalanus balanoides in which latitudinal variation in timing of egg mass hardening has been examined simultaneously over the geographical scale involved, thereby excluding temporal confounding of the data. The timing of autumn egg mass hardening on the middle shore was established in 2002 and 2003 at ten stations ranging latitudinally from Trondheim (63°24′N) to Plymouth (50°18′N). To assess variation at local scale (<10 km), breeding was studied on three shores at each of two Irish locations (Cork and Galway). At Oban (Scotland) and Cork, the effect of shore height on timing of breeding was investigated. A strong influence of latitude and day length on timing of breeding was found in both 2002 and 2003. In both years, barnacles bred much earlier (when day length was longer) at high rather than low latitudes. No significant effect of environmental temperature or insolation on timing of breeding was detected. Shores no more than 10 km apart showed minimal difference in middle shore breeding date (<4 days). However, upper shore barnacles bred significantly earlier (by 7–13 days) than middle shore animals. The data indicate that breeding is controlled by period of daily darkness, with high shore animals encountering longer effective ‘nights’ because of the opercular closure response to emersion (which will reduce light penetration to tissues). Predictions concerning the effects of global changes in climate and cloud cover on breeding and population distribution are made. It is suggested that increased cloud cover in the northern hemisphere is likely to induce earlier breeding, and possibly shift the present southern limit of Semibalanus southwards.
Design space explorers are computer programs that play
on an exploration metaphor to support design.
They assist designers in creating alternative designs by
structuring the process of design creation in a space of
alternatives. Subsidiary metaphors relevant to design space
explorers are generation, navigation,
and reuse. This paper introduces, in two sketches,
typed feature structures as a formal system in which a
design space explorer and its knowledge level might be
implemented. First, informal and abstract properties of
typed feature structures suffice to build a sketch of the
behavior of a design space explorer. Second, using an example
based on single-fronted cottages (a common Australian housing
type), we outline the typed feature structure machinery
most relevant to design space exploration.
Substance use disorder (SUD) pedigrees identified through an attention deficit/hyperactivity disorder (ADHD) proband may be helpful in teasing apart the genetic risks for both ADHD and SUD (ie, alcohol or drug use). Pedigrees segregating for both SUD and ADHD may represent a subset of both of these common disorders that share a related genetic basis. We determined the number of SUD and ADHD pedigrees in a sample of 175 ADHD probands. We found 52 ADHD pedigrees, indicating that at least 29.7% were familial cases. We also found 50 SUD pedigrees; 13 families contained both an alcohol and a drug pedigree, 35 families were alcohol-only pedigrees, and two families were drug-only pedigrees. The incidence of drug-only pedigrees is significantly higher (P<0.01) in families with familial ADHD. This was also true for families with both drug and alcohol pedigrees (P<0.01). The total number of SUD pedigrees and the families with alcohol-alone pedigrees were not significantly different in ADHD pedigrees compared with nonfamilial ADHD families.
Buried individuals of the bivalve Donax vittatus (Bivalvia: Donacidae) respond to change in incident light intensity by adjusting their position in the sediment. Video recordings of activity in aquarium tanks in natural daylight revealed that individuals responded to shading by moving upwards, causing some to partially emerge from the sand. Subsequent removal of the shading stimulated reburial to the normal position. Recordings in laboratory aquaria show similar upward movement and partial emergence occurring when illumination in the visible range is switched off. Upward movement and partial emergence of D. vittatus has also been observed to take place prior to spawning.
Most of the mass near the Sun takes the form of stars less luminous than the Sun. A central problem of Galactic astronomy is the determination of how much mass these stars contain.
The only thoroughly reliable way of detecting mass is through its gravitational field. Classically this has been done by studying the Galaxy’s rotation curve and the Oort limit, both of which remain active areas of research. In the last few years an exciting new way of probing the Galaxy’s gravitational field has been opened up by large surveys for microlensing events. These surveys are yielding important information about the numbers of low-mass objects both in the disk and above it. Another truly dynamical probe for low-luminosity objects is provided by studies of clusters. JD 10 reviewed what we have learned about the density of low-luminosity stars from each of these approaches.
An important orthogonal approach to determining the density of low-luminosity stars involves seperately determining the luminosity function and the mass-luminosity relation for stars of a given spectral class (e.g. main-sequence stars) and then combining them to obtain the mass function. The development of infrared detectors and the refurbishment of the The Hubble Space Telescope have recently yielded important advances in each of these areas. A major difficulty with this line of research is the fact that, in the neighbourhood of M = 0.08 Mʘ, the main-sequence mass-luminosity relation is (i) steep and non-linear, and (ii) dependent not only on the masses of the faintest stars, but also on their ages, metallicities, rotation rates, binarity etc. Moreover, cool low-luminosity stars have extremely complex spectra, which are difficult to simulate with radiative transfer calculations. Similar difficulties are encountered in the determination of the mass-luminosity relation for white dwarfs. JD 10 reviewed the current status of these very difficult problems.
A cDNA clone encoding a full length putative collagen has been isolated in a screen of a mixed stage Globodera pallida expression library. Comparison of the deduced amino acid sequence of this molecule with other collagens suggests it is a cuticular collagen and a member of the col-8 subfamily of collagen genes. Northern blots show the gene is expressed specifically in gravid, adult females of the parasite as compared to second (invasive) stage juveniles and virgin females. Preliminary immunocytochemical studies indicate this collagen is present in areas other than the cuticle; these findings and the potential functional role of this collagen are discussed.
DNA from species and races of plant parasitic nematodes (Meloidogyne, Globodera and Heterodera) and a human parasitic nematode (Trichinella) were subjected to polymerase chain reaction amplification using one arbitrary primer (M-10). This technique results in relatively simple DNA profiles that include polymorphic markers known as random amplified polymorphic DNA (RAPDs). The RAPD profiles of the plant nematode species of Meloidogyne made possible the identification of M. incognita and M. hapla, but no differences were found between the patterns of M. javanica, M. arenaria and M. graminicola. Moreover, the four races of M. incognita were indistinguishable by this primer. In contrast, when races of the plant nematode Globodera rostochiensis (Ro1 and Ro2/3) were studied under the same RAPDs conditions, a race specific profile allows these two most devastating races to be differentiated. When DNAs of eight Trichinella isolates were subjected to RAPD studies, four different patterns were identified, corresponding to the four Trichinella clusters previously defined by isozyme polymorphism.
A genomic library of Meloidogyne incognita Race 1 has been prepared in the bacteriophage λgt10 and screened for specific DNA sequences by hybridization with radio-isotope labelled total genomic DNA from a number of Meloidogyne species. One clone isolated (MR1#15), although not totally species specific, clearly showed preferential hybridization to M. incognita. Following subcloning and sequencing of the 255 bp insert, four stretches of the sequence corresponding to oligonucleotides of approximately equal length (~60 bp) were synthesized and examined for specificity. One of them, MR1#15.2, showed the necessary specificity to be used as a diagnostic tool.
Stage-2 nauplii larvae were taken in near-surface inshore tow-nets on the Northumberland coast in January and February of 1986, confirming isolated reports of similar observations in 1979–80. These occurrences are much earlier than expected from the normally described progression of naupliar release in British waters. It is suggested that premature larval release may be occasioned by damage to, or predation on, parent colonies.