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Lying at the southernmost point of the Lucayan Archipelago, the Turks and Caicos Islands are amongst the better studied localities for anchialine cave biodiversity. For nearly five decades, novel invertebrate fauna, comprised primarily of crustaceans, have been collected from these tidally influenced pools – but new findings are always on the horizon. Herein we present new records of crustaceans and annelids from anchialine blue holes and horizontal caves of the Turks and Caicos. These findings include two potentially new species of meiofaunal annelids and a new species of remipede collected from a shallow water cave pool. Our 2019 expedition additionally expands known faunal distributions for several taxa across the Caicos islands, and raises the biodiversity of the region to 35 species, 13 of them considered endemic. This is the first comprehensive faunal list for the anchialine systems in the Caicos Bank.

Background A more accurate means of prognostication in breast cancer will improve the selection of patients for adjuvant systemic therapy. Methods Using microarray analysis to evaluate our previously established 70-gene prognosis profile, we classified a series of 295 consecutive patients with primary breast carcinomas as having a gene-expression signature associated with either a poor prognosis or a good prognosis. All patients had stage I or II breast cancer and were younger than 53 years old; 151 had lymph-node–negative disease, and 144 had lymph-node–positive disease. We evaluated the predictive power of the prognosis profile using univariable and multivariable statistical analyses. Results Among the 295 patients, 180 had a poor-prognosis signature and 115 had a good-prognosis signature, and the mean (±SE) overall 10-year survival rates were 54.6±4.4 percent and 94.5±2.6 percent, respectively. At 10 years, the probability of remaining free of distant metastases was 50.6±4.5 percent in the group with a poor-prognosis signature and 85.2±4.3 percent in the group with a good-prognosis signature. The estimated hazard ratio for distant metastases in the group with a poor-prognosis signature, as compared with the group with the good-prognosis signature, was 5.1 (95 percent confidence interval, 2.9 to 9.0; P

BAC transgenesis in mice has proved to be useful in exploring the regulatory mechanisms and functions of the Hox complexes. The large constructs used may include most of the relevant components of the cis-regulatory landscape. Manipulations can be accomplished without compromising the integrity of the endogenous complex which reduces the likelihood of producing confounding phenotypic abnormalities. The development of recombineering tools has been critical in providing the means necessary to make many types of precise and varied manipulations of these large constructs. Here, we will discuss the methodologies necessary to manipulate Hox complex BACs, generation of transgenic animals bearing these constructs and the utilization of these resources to address fundamental aspects of Hox biology.

We established that the choice of the laboratory mill has little effect on steam-distillable volatile oil (VOSD) analysis of Cassia bark when reasonable care is used in preparing single samples. When multiple samples are milled, caution is advised to avoid temperature increase. Data from 11 laboratories are presented for 4 test samples. Participating laboratories milled 200 g samples, and the variation of the resulting VOSD in the ground spice could not be attributed to the different grind-size profiles measured. The estimated systematic error due to type of mill was 0.04 mL/100 g. This represents a relative standard deviation of 2.2% for the lowest average volatile oil levels.

The olfactory bulb (OB) is a laminar structure containing two distinct neuronal populations. Excitatory projection neurons populate the mitral cell layer (MCL), and interneuron populations are located in the glomerular layer (GL) and granule cell layer (GCL), superficial and deep to the MCL respectively. OB neuronal populations are sequentially produced and have distinct origins. Mitral cells are the firstborn OB population (Hinds, 1968). These cells arise in the pallium, and the transcription factor Tbr1 is required for their generation (Bulfone et al., 1998; Moreno et al., 2003; Puelles et al., 2000). OB interneurons arise from an ER81-positive population in the subpallial dorsal lateral ganglionic eminence (LGE) and migrate to the OB via the rostral migratory stream (RMS; Doetsch and Alvarez-Buylla, 1996; Lois and Alvarez-Buylla, 1994; Stenman et al., 2003; Wichterle et al., 1999, 2001). Previous studies determined that OB interneurons are continuously generated throughout life (Altman, 1969; Altman and Das, 1966; Doetsch and Alvarez-Buylla, 1996; Hinds, 1968; Lois and Alvarez-Buylla, 1994; Luskin, 1993); however, mechanisms that regulate the generation of this diverse cellular population are not well characterized. OB interneurons begin to express mature interneuron markers as they terminally differentiate and radially migrate in the OB. The OB comprises chemically distinct interneuron populations; at least three subtypes have been identified characterized by γ-aminobutyric acid (GABA), calretinin, and calbindin expression (Kosaka et al., 1995; Toida et al., 2000). Cells in the GCL homogenously express GABA (Parrish-Aungst et al., 2007). Within the GL, GABA, calretinin, and calbindin are expressed by ~20–53%, ~20–27%, and ~10% of neurons, respectively (Kosaka et al., 1995; Parrish-Aungst et al., 2007). The remaining interneuron populations in this layer have not yet been chemically distinguished. The GABAergic population can be further divided into dopaminergic and nondopaminergic populations, characterized by the expression of tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine biosynthesis; ~80% of dopaminergic cells are also GABAergic (Hack et al., 2005; Kosaka et al., 1998; Parrish-Aungst et al., 2007), and 95% of TH-positive cells in the GL are Pax6-positive (Hack et al., 2005). Little overlap is observed between the TH/Pax6 populations and the calretinin (~2% overlap with Pax6)/calbindin (~10% overlap with Pax6)-positive populations (Hack et al., 2005; Kosaka et al., 1995, 1998; Waclaw et al., 2006). In addition, examination of the temporal specification of OB interneurons has identified overlap in the timing of birth of these chemically diverse populations (Tucker et al., 2006). These findings suggest that intrinsic factors play an important role in OB interneuron specification, insofar as diverse interneuron populations born at the same time would be exposed to similar extrinsic cues. Insight into the mechanisms that regulate production of interneuron populations destined for the OB has been obtained from analyses of murine knockout models (Soria et al., 2004; Stenman et al., 2003; Waclaw et al., 2006; Yoshihara et al., 2005; Yun et al., 2003). These studies have demonstrated that interneuron generation can be divided into the following steps; specification of interneuron progenitors within the LGE, entry from the LGE to the RMS, migration in the RMS, exit from the RMS to the OB, radial migration within the OB, and terminal differentiation. The transcription factors Sp8 (Waclaw et al., 2006) and GSH1/2 (Stenman et al., 2003; Yun et al., 2003) are required for the initial specification of OB progenitors in the LGE. Vax1 is necessary for the transition of cells from the LGE to the RMS (Soria et al., 2004). The secreted protein Slit has been implicated in the migration of inter-neurons via the RMS (Chen et al., 2001; Hu, 1999; Wu et al., 1999), and the homeobox protein ARX is required for the entry of interneurons from the RMS to the OB (Yoshihara et al., 2005). Furthermore, Pax6 has been implicated in the generation of dopaminergic OB interneurons (Hack et al., 2005; Kohwi et al., 2005). Thus, we are beginning to understand components of OB cell type generation and migration within the RMS; however, mechanisms regulating terminal differentiation and maturation within the OB are not well characterized. We examined the role of Sall3 in the development of the olfactory system. Sall3 is one of four mammalian members of the Sall gene family, which are widely expressed throughout development, in the peripheral and central nervous system as well as in peripheral organs (Al-Baradie et al., 2002; Buck et al., 2000, 2001; Kohlhase et al., 1996, 1999, 2000, 2002a,b; Ott et al., 1996, 2001). Distinct developmental disorders with some overlapping characteristics are associated with mutation or deletion of members of this gene family in humans (Al-Baradie et al., 2002; Kohlhase et al., 1998, 1999, 2002b). SALL3 is one of several genes deleted in 18q deletion syndrome, characterized by hearing loss, mental retardation, midfacial hypoplasia, delayed growth, and limb abnormalities (Jayarajan et al., 2000; Kohlhase et al., 1999; Mahr et al., 1996; Strathdee et al., 1997; Verhoeven et al., 2006; Wilson et al., 1979). The Sall genes are zinc finger-containing putative transcription factors (Kuhnlein et al., 1994). They have been shown to localize to heterochromatin (Netzer et al., 2001; Sakaki-Yumoto et al., 2006; Sato et al., 2004), and it is hypothesized that they can mediate transcriptional repression via recruitment of histone deacetylase (Kiefer et al., 2002; Lauberth and Rauchman, 2006). Members of the Sall gene family can interact at the protein level (Kiefer et al., 2002; Sakaki-Yumoto et al., 2006; Sweetman et al., 2003) and have been implicated in diverse cellular processes, including cell cycle regulation, cell fate specification, neuronal differentiation, migration, and cell adhesion (Barembaum and Bronner-Fraser, 2004; Bohm et al., 2007; Cantera et al., 2002; de Celis et al., 1999; Franch-Marro and Casanova, 2002; Jurgens, 1988; Kuhnlein and Schuh, 1996; Toker et al., 2003). These data suggest the members of the Sall gene family are important developmental regulators. We have previously shown that Sall3 (previously named msal1) is expressed during olfactory development (Ott et al., 1996, 2001), although a detailed description has not been given. We determined that Sall3 was expressed by cells within the OB and olfactory epithelium. Within the OB, Sall3 was expressed by progenitor cells and subpopulations of differentiated neurons. Sall3-deficient animals die perinatally (Parrish et al., 2004), and we examined development of the olfactory system to P0.5. We identified alterations in interneuron development in Sall3 mutant animals. Our data suggest that Sall3 is required for the terminal maturation of GL interneurons in the developing OB.

Members of the Spalt gene family encode putative transcription factors characterized by seven to nine C2H2 zinc finger motifs. Four genes have been identified in mice--Spalt1 to Spalt4 (Sall1 to Sall4). Spalt homologues are widely expressed in neural and mesodermal tissues during early embryogenesis. Sall3 is normally expressed in mice from embryonic day 7 (E7) in the neural ectoderm and primitive streak and subsequently in the brain, peripheral nerves, spinal cord, limb buds, palate, heart, and otic vesicles. We have generated a targeted disruption of Sall3 in mice. Homozygous mutant animals die on the first postnatal day and fail to feed. Examination of the oral structures of these animals revealed that abnormalities were present in the palate and epiglottis from E16.5. In E10.5 embryos, deficiencies in cranial nerves that normally innervate oral structures, particularly the glossopharyngeal nerve (IX), were observed. These studies indicate that Sall3 is required for the development of nerves that are derived from the hindbrain and for the formation of adjacent branchial arch derivatives.

We have identified a new member of the spalt-like gene family in mice, msal-3. We compared the expression patterns of msal-3 and msal-1 during development and show that they exhibit overlapping yet exclusive patterns of expression in the developing forebrain, diencephalon, midbrain/hindbrain boundary and spinal cord. Both genes are expressed from E7 in opposite gradients in primitive streak mesoderm. Subsequently their transcripts are localized to regions of mesenchyme/epithelial interaction in the palate, heart, limbs, anal and urogenital region.

Tubular ectasia of the rete testis is an uncommon entity that is usually discovered incidentally during ultrasound evaluation of epididymal abnormalities. The characteristic ultrasound appearance, its frequent association with spermatoceles and the lack of a palpable mass are the main features that permit identification of this entirely benign lesion.

Operations systems (OSs) have assumed an expanded role in the network and are instrumental in providing increasingly complex services. Therefore, a strategy was needed to be able to develop a new high-quality OS or upgrade an existing one in a cost-effective and timely way. This strategy includes a standard AT&T operating environment and a modular software architecture that emphasizes large-scale module reuse and layered virtual machines. With this base, operations systems will be able to respond effectively to future network needs. This article discusses the architecture of TOPAS, which is a primary example of an advanced operations system. Because of its modular design, considerable TOPAS software was reused in TMAS, another operations system.

General experimental results are presented on the environmental effect exerted by nitrogen and argon on the tensile deformation of polymers in the neighborhood of 80° K. The primary features are the large dependence of tensile strength on strain rate and the occurrence of crazing, both of which are absent in helium and vacuum environments. The fracture stress in N2 and Ar may be less or greater than that in He and vacuum in accordance with the strain rate being low or high, respectively. A brief theory for the low-temperature environmental crazing is presented. A central part of the theory is related to the fact that the adsorption of N2 and Ar on all polymers around 80° K substantially reduces their surface free-energy by about 25 to 75%.

The object of this investigation was to determine the origin of deformation bands in one-way oriented polyethylene terephthalate (PET) and their relation to the upper yield point. The tensile yield point was measured at room temperature as a function of the angle (θ) between the original draw direction and the tensile axis. The effect of strain rate was observed. The growth and geometry of deformation bands were studied. The results showed that the formation of a deformation band in PET cannot be interpreted as the strength-limiting yield mechanism for all θ and that the viscoelastic behavior plays the primary part in determining the yield point of this semicrystalline polymer.

The effect of N2 Ar, and He on the tensile stress-strain behavior of various polymers at about 78°K is presented. N2 and Ar cause crazing and modify the stress-strain curve, whereas He is inert, like a vacuum. A theory of the environmental effect is given which is based on the adsorption of N2 and Ar on polymers and on the fact that they undergo a large fractional decrease in their surface energy.

IT is generally thought that having a polymer immersed in liquid nitrogen does not affect its stress-strain behaviour. We found that liquid and gaseous nitrogen and liquid argon affect the tensile stress-strain curve and the mode of fracture of amorphous polymers. Previous investigations at ∼78 K of the tensile behaviour of amorphous polymers have been conducted in liquid or gaseous nitrogen. Polymethyl methacrylate (PMMA), when stretched in liquid nitrogen, showed severe crazing1 with increased fracture toughness at 78 K. Beardmore and Johnston2 and Beardmore3 investigated PMMA tested in tension at 78° C; in the former paper no mention was made of test environment; in the latter paper, the specimen was surrounded with lead shot cooled with liquid nitrogen. Beardmore and Rabinowitz4 studied tensile crazing of PMMA, polycarbonate (PC) and polysulphone (PSF) at 78 K, but they did not specify the environment (S. Rabinowitz, private communication). Ekvall and Low5 studied PC from 78 to 300 K in nitrogen gas and found a ductile-to-brittle transition between 90 K and 143 K. Our work suggests that this transition was an environmental effect of the nitrogen gas.