Effects of Dissolved Oxygen on Northern Leopard Frog (Lithobates pipiens) Gastrocnemius Muscle Recruitment and Fatigue

Dissolved oxygen levels in aquatic systems have decreased because of temperature increases caused by climate change, which in turn has affected ecosystems and wildlife. Many physiological processes in aquatic organisms require a certain dissolved-oxygen range, and decreasing levels can compromise proper functioning. Previous studies have linked muscle performance to dissolved oxygen levels in a variety of aquatic species, but less research has been dedicated to amphibians. Because many amphibians engage in cutaneous respiration, especially when dwelling in aquatic habitats, dissolved oxygen levels may have a significant impact on muscle performance in this taxon. This experiment investigated the effects of dissolved oxygen and time in vitro on frog skeletal muscle contractile force and fatigue. Results did not vary significantly when dissolved oxygen was altered, but fatigue and contractile force experiments did correlate with time in vitro. Although we did not find an effect of dissolved oxygen levels on muscle characteristics in vitro, a better understanding of the effects of dissolved oxygen on muscle performance, particularly in vivo, could be beneficial as climate change alters the oxygen content of aquatic systems, with the potential to affect physiology and behavior. Keywords: cutaneous respiration, dissolved oxygen, contractile force, fatigue, in vitr

Faktor Yang Berhubungan Dengan Sanitasi Depot Air Minum Di Wilayah Kerja Puskesmas Andalas Kecamatan Padang Timur Tahun 2018

Tujuan Penelitian Sanitasi depot air minum tidak semua yang dikelola dengan baik, dari observasi awal ditemukan 50% sanitasi depot air minum tidak sesuai dengan keputusan Menteri Perindustrian dan Perdagangan RI Nomor 651/mpp/kep/10/2004 tentang persyaratan teknis depot air minum dan perdagangan menteri perindustrian dan perdagangan. Tujuan penelitian ini adalah menganalisis faktor yang berhubungan dengan sanitasi depot air minum di wilayah kerja Puskesmas Andalas Kecamatan Padang Timur tahun 2018. Metode Penelitian Desain penelitian ini adalah kuantitatif dengan teknik cross sectional. Populasi pada penelitian ini sebanyak 74 depot air minum dengan sampel 36 depot air minum. Pengumpulan data dilakukan dengan observasi dan pengisian kuesioner. Data diambil dengan systematic random sampling di wilayah kerja Puskesmas Andalas Kecamatan Padang Timur yang dilaksanakan pada bulan 23 April – 25 Mei tahun 2018. Hasil Berdasarkan hasil penelitian didapatkan sebesar 22,2% sanitasi depot air minum dalam keadaan kurang baik, 41,7% pengetahuan responden rendah, 58,3% sikap responden negatif, 13,9% tindakan responden yang tidak baik, dan 63,9% pengawasan tidak baik. Hasil analisis bivariat dengan uji kai kuadrat didapatkan hubungan yang bermakna antara pengetahuan (p= 0,046) terhadap senitasi depot. Tidak terdapat hubungan yang bermakna antara sikap (p=0,424), tindakan (p=1,000) dan pengawasan (p= 0,213) dengan sanitasi depot. Kesimpulan Masih banyak depot air minum isi ulang yang sanitasinya kurang baik, baik dari segi pengetahuan petugas, sikap petugas, tindakan petugas dan pengawasan yang masih kurang.Untuk menjaga sanitasi depot dan kualitas air minum yang dikonsumsi masyarakat dilakukanlah pengawasan secara ketat baik itu dari pihak penyelenggara DAMIU maupun dari pihak pemerintah. Daftar Pustaka : 35 (2001-2016) Kata Kunci : Sanitasi, depot air minum, Pengawasa

KAJIAN STRUKTUR DAN UNSUR NILAI MORAL CERITA ASAL USUL DESA NAMANG SERTA IMPLIKASINYA SEBAGAI BAHAN AJAR DI SMP

Penelitian ini dilatarbelakangi oleh cerita sulitnya air di bagian tengah pulau Bangka dan belum berkembangnya bahan ajar berbentuk digital. Hasil pengkajian struktur cerita dan nilai moral dari cerita “Asal Usul Desa Namang”. Tujuan penelitian skripsi ini mendeskripsikan struktur cerita “Asal Usul Desa Namang”, mendeskripsikan nilai moral cerita “Asal Usul Desa Namang”, dan merancang bahan ajar berbentuk komik digital. Penelitian ini menggunakan metode deskriptif kualitatif. Hasil pengkajian struktur cerita “Asal Usul Desa Namang” yaitu: Alur pada cerita ini diawali dengan pengenalan masalah dan diakhiri dengan pemecahan masalah, Karakter yang tergambar pada cerita ini adalah sosok Bujang yang menjadi tokoh utama, Latar tempat di pulau Bangka, Latar sosial dalam cerita berhubungan dalam kehidupan sosial masyarakat menggambarkan kesulitan dalam mendapatkan air saat musim paceklik, Tema cerita “Asal Usul Desa Namang” yaitu kedermawanan, Sudut pandang yang ada dalam cerita adalah sudut pandang orang ketiga serba tahu, Gaya bahasa pengarang sangat mudah dipahami, Tone cerita ini yaitu, haru, sedih, bangga, dan penuh perasaan, yakni sosok pemuda yang baik hati, dermawan, dan bertelanjang dada ketika melayani para orang tua mengambil air, Ironi dalam cerita adalah ironi dramatis, dan Judul “Asal Usul Desa Namang” sesuai dengan pemberian nama desa yang dikenal dengan gemar memberikan pertolongan kepada orang lain. Hasil analisis terhadap nilai moral didapatkan beberapa hal, di antaranya kejujuran, menjadi diri sendiri, bertanggung jawab, kemandirian, keberanian moral, kerendahan hati, dan kritis. Bahan ajar yang dirancang yaitu, berbentuk komik digital dalam format PDF dan ditujukan untuk siswa tingkat Sekolah Menengah Pertama (SMP)

Effects of the invasive aquatic snail Potamopyrgus antipodarum (Gray, 1853) on ecosystem properties and services

Ecosystems provide benefits to humans, including provisioning, regulating, and cultural services. However, invasive species can threaten ecosystem well-functioning and services provided. One invasive species with such potential is the New Zealand mud snail (NZMS) Potamopyrgus antipodarum. The aims of this study are focused on the quantitative review of (1) the NZMS impacts on ecosystem properties and their direct links with ecosystem services, and (2) the ecosystem services that can be affected by the NZMS. The high density reached by this species in most of the invaded ecosystems and its highly competitive ability affect ecosystem structure and functioning. However, some facilitation processes on native species may result in an improvement of some services. The NZMS tends to positively affect cultural services (88% positive cases) but negatively to provisioning services (77% of cases). Regarding, regulating and maintenance services, the proportions of positive and negative effects were similar (45% vs 36%, respectively). Therefore, the NZMS is a species with numerous negative impacts on ecosystem services. However, ecosystem services related to health (e.g., dilution effect against parasites) and research (e.g., biomonitoring) are cultural services that the NZMS can improve. No economic assessment of the impacts of the NZMS is available in the literature

Young Aphids Avoid Erroneous Dropping when Evading Mammalian Herbivores by Combining Input from Two Sensory Modalities

Mammalian herbivores may incidentally ingest plant-dwelling insects while foraging. Adult pea aphids (Acyrthosiphon pisum) avoid this danger by dropping off their host plant after sensing the herbivore's warm and humid breath and the vibrations it causes while feeding. Aphid nymphs may also drop (to escape insect enemies), but because of their slow movement, have a lower chance of finding a new plant. We compared dropping rates of first-instar nymphs with those of adults, after exposing pea aphids to different combinations of simulated mammalian breath and vibrations. We hypothesized that nymphs would compensate for the greater risk they face on the ground by interpreting more conservatively the mammalian herbivore cues they perceive. Most adults dropped in response to breath alone, but nymphs rarely did so. Breath stimulus accompanied by one concurrent vibrational stimulus, caused a minor rise in adult dropping rates. Adding a second vibration during breath had no additional effect on adults. The nymphs, however, relied on a combination of the two types of stimuli, with a threefold increase in dropping rates when the breath was accompanied by one vibration, and a further doubling of dropping rates when the second vibration was added. The age-specificity of the aphids' herbivore detection mechanism is probably an adaptation to the different cost of dropping for the different age groups. Relying on a combination of stimuli from two sensory modalities enables the vulnerable nymphs to avoid costly mistakes. Our findings emphasize the importance of the direct trophic effect of mammalian herbivory for plant-dwelling insects

The best of both worlds? A review of delayed selfing in flowering plants

PREMISE OF STUDY: In a seminal body of theory, Lloyd showed that the fitness consequences of selfing will depend on its timing in anthesis. Selfing that occurs after opportunities for outcrossing or pollen dispersal can provide reproductive assurance when pollinators are limited and is expected to incur little cost, even when inbreeding depression is high. As a result, delayed selfing is often interpreted as a “best-of-both-worlds� mating system that combines the advantages of selfing and outcrossing. METHODS: We surveyed 65 empirical studies of delayed selfing, recording floral mechanisms and examining information on inbreeding depression, autofertility, and other parameters to test the support for delayed selfing as a best-of-both-worlds strategy. KEY RESULTS: Phylogenetic distribution of the diverse floral mechanisms suggests that some basic floral structures may predispose plant taxa to evolve delayed selfing. Delayed selfing appears to serve as a best-of-both-worlds strategy in some but not all species. While the capacity for autonomous selfing is often high, it is lower, in some cases, than in related species with earlier modes of selfing. In other delayed-selfers, low inbreeding depression and reduced investment in corollas and pollen suggest limited benefits from outcrossing. CONCLUSIONS: Despite a growing literature on the subject, experimental evidence for delayed selfing is limited and major gaps in knowledge remain, particularly with respect to the stability of delayed selfing and the conditions that may favor transitions between delayed and earlier selfing. Finally, we suggest a potential role of delayed selfing in facilitating transitions from self-incompatibility to selfing