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Harmful algal blooms (HABs) are naturally occurring phenomena, and cyanobacteria are the most commonly occurring HABs in freshwater systems. Cyanobacteria HABs (cyanoHABs) negatively affect ecosystems and drinking water resources through the production of potent toxins. Furthermore, the frequency, duration, and distribution of cyanoHABs are increasing, and conditions that favor cyanobacteria growth are predicted to increase in the coming years. Current methods for mitigating cyanoHABs are generally short-lived and resource-intensive, and have negative impacts on non-target species. Cyanophages (viruses that specifically target cyanobacteria) have the potential to provide a highly specific control strategy with minimal impacts on non-target species and propagation in the environment. A detailed review (primarily up to 2020) of cyanophage lifecycle, diversity, and factors influencing infectivity is provided in this paper, along with a discussion of cyanophage and host cyanobacteria relationships for seven prominent cyanoHAB-forming genera in North America, including: Synechococcus, Microcystis, Dolichospermum, Aphanizomenon, Cylindrospermopsis, Planktothrix, and Lyngbya. Lastly, factors affecting the potential application of cyanophages as a cyanoHAB control strategy are discussed, including efficacy considerations, optimization, and scalability for large-scale applications.  相似文献   
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In the last decade, public attention to the problem of commercially sexually exploited children (CSEC) has grown. This exploratory qualitative study examines adolescent pimping relationships, including how urban youth perceive these types of relationships. Study data stem from interviews with three young adult informants with first-hand knowledge of adolescent pimping, as well as three gender-specific focus group discussions with a convenience sample of 26 urban high school students who have first- or second-hand knowledge of adolescent pimping. Findings indicate that respondents believe teen pimping exists in their schools and communities, and that those exploited typically do not self-identify as victims. Respondents also believed that younger pimps are more likely to use violence to induce compliance among the girls they exploit, whereas older pimps are more likely to emotionally manipulate young women into exploitation. Further, respondents indicated that some young people agreed to exchange or sell sex for money as a favor to their boyfriends or girlfriends, and some young people believed that selling sex is acceptable under certain circumstances. The growing attention to CSEC provides an important opportunity to expand prevention efforts to reach those most affected and at risk for exploitation. The findings highlight critical areas for augmenting traditional content in school-based HIV/STI and sexuality education classes.  相似文献   
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Optic disc pit (ODP) is small, gray-white, oval depression found at the optic nerve head. It is a congenital defect that occurs due to imperfect closure of superior edge of the embryonic fissure. Cleft lip and palate are also congenital midline abnormalities occurring due to defect in the fusion of frontonasal prominence, maxillary prominence and mandibular prominence. There is only one case report describing the occurrence of ODP in a young patient with cleft lip and palate who also had basal encephalocele. We describe a 52-year-old patient with congenital cleft lip and palate with bilateral ODP with maculopathy but without any other midline abnormality.  相似文献   
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During routine monitoring of yellow-crowned parakeets in the Poulter Valley of the South Island of New Zealand, a dead parakeet chick was discovered in a nest. Known parrot-infecting viruses, such as beak and feather disease virus (BFDV), avian polyomavirus (APV), and parrot hepatitis B virus (PHBV), were not detected in the nesting material. However, we recovered two novel single-stranded DNA viruses (ssDNA), CynNCXV (2308 nt) and CynNCKV (2087 nt), which have genome architectures similar to those of circoviruses, characterised by circular genomes with two large bidirectional open reading frames (ORFs). Both contain a stem-loop element with a conserved nonanucleotide motif, known to be required for rolling-circle replication. The full genomes had no BLASTn similarity to known ssDNA viruses. However, in both genomes the larger ORFs have BLAST similarity to known replication-associated proteins (Reps). CynNCKV has 30 % similarity to picobiliphyte nano-like virus (Picobiliphyte M5584-5) with 66-88 % coverage (e-value of 5×10?33), whereas CynNCXV has 33 % similarity to rodent stool-associated virus (RodSCV M-45) with 92-94 % coverage (e-value of 5 × 10?31). Found within these ORFs were the rolling-circle replication motifs I, II, III and the helicase motifs Walker A and Walker B. Maximum-likelihood phylogenetic analysis of the Reps reveals that these are two novel ssDNA viruses. At this point, we are unable to attribute the death of the parakeet to these two new novel ssDNA viruses.  相似文献   
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  • Diabetic patients are frequently affected by coronary artery disease (CAD) and are at increased risk of CAD‐related adverse events, even after drug‐eluting stent (DES) implantation. If currently available DES have similar safety and efficacy in diabetic and nondiabetic patients is still debated.
  • This prospective, multicenter registry showed similar 3‐year outcome in patients undergoing different DES implantation, although diabetic patients, especially those requiring insulin treatment, had significantly higher risk of adverse events than nondiabetic patients.
  • Specific efforts to improve the performance of DES in diabetic patients are mandatory to adequately address the unsolved issue of diabetic patients affected by CAD.
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A 33 years old female patient presented with posttraumatic pain in the right foot for which radiographs of the right foot was advised. No fracture was detected on radiographs and patient was managed conservatively on medications and posterior splint immobilization. We found coincidentally a short fourth metatarsal and an accessory navicular bone in the right foot radiographs. After 3 weeks of immobilization, she underwent mobilization of the right foot, weight bearing and intensive physiotherapy for 6 weeks. After two months of injury she was still complaining of pain on the plantar aspect of right foot which was diagnosed as metatarsalgia and operated on by excision of the neuroma present in the 3rd web space of the right foot. After surgery she was completely relieved of pain and could do activities well related to the right foot.  相似文献   
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Latinos in the U.S. are disproportionately affected by HIV and are more likely than non-Latinos to present with a late diagnosis, which delays engagement in HIV care and treatment. Social networks may provide normative influence and social support for HIV testing, but a contextualised understanding of networks is needed in order to maximise these social resources. We conducted qualitative interviews with foreign-born Latino men and transgender women (n?=?17) in a new immigrant destination to explore their social networks. Most participants described having smaller social networks after migrating. Networks included both local and transnational ties, but most participants had few close ties. Contextual factors including stigma and geographic dispersion limited the re-construction of networks with close ties after migration. HIV testing was not a common topic of discussion with social network ties. Efforts to improve early uptake of HIV testing among Latino immigrants may benefit from engaging with social networks, but such efforts need to address how the context in which networks operate enables access to testing.  相似文献   
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