The Acceleration of the Expansion of the Universe: A Brief Early History of the Supernova Cosmology Project (SCP)

It is now about 10 years since the evidence, based on Type Ia supernovae, for the acceleration of the expansion of the Universe was discovered. I will discuss some aspects of the work and events in the Supernova Cosmology Project (SCP), during the period 1988 to 1998, which led to this discovery.Comment: 20 pages, 10 figures. To appear in the Proceedings of the 8th UCLA Dark Matter Symposium, Marina del Rey, USA, 20-22 February 2008. Revision with references corrected, new references added, and minor text update

Social Media Usage Patterns: Research Note Regarding the Lack of Universal Validated Measures for Active and Passive Use

The existing literature regarding social media use provides extant evidence supporting the claim that usage patterns ultimately have the capability of impacting users. However, the vast majority of the literature is based upon experimental laboratory settings where participants are observed by researchers. The current article asserts that there is a significant deficiency within the discipline regarding the validated measurement of usage patterns of social networking sites (SNSs) and offers guidance for those who may want to develop a general measure

Lende Ura, sebuah Inisiatif Masyarakat dalam Rehabilitasi Hutan dan Lahan di Sumba Barat Daya

Masyarakat lokal memiliki peran strategis dalam mendukung kegiatan rehabilitasi hutan dan lahan. Berbagai pola adaptasi masyarakat lokal terhadap lingkungan merupakan salah satu sumberdaya yang perlu mendapatkan perhatian dalam perencanaan pembangunan kehutanan berkelanjutan. Manusia tidak dapat dipisahkan dari lingkungannya, dan sebaliknya manusia adalah produk dari lingkungan, sehingga berbagai bentuk adaptasi lingkungan banyak dijumpai berdasarkan persepsi dan pengalaman berinteraksi dalam pengelolaan dan pemanfaatan sumberdaya hutan, tanah dan air. Inisiatif lokal pada tataran filosofis maupun praktis, sesungguhnya merupakan modal dasar bagi pembangunan. Penelitian ini mengkaji tentang inisiatif lokal Lende Ura yang ada pada masyarakat Sumba Barat Daya, Nusa Tenggara Timur (NTT). Penelitian menggunakan pendekatan deskriptif melalui pendokumentasian literatur dan wawancara mendalam terkait fokus kajian. Penelitian dilakukan tahun 2009. Analisis data dilakukan secara deskriptif naratif. Lende Ura merupakan salah satu bentuk inisiatif lokal yaitu sebuah filosofi kehidupan masyarakat di Sumba Barat Daya yang memandang hutan sebagai jembatan bagi datangnya hujan. Masyarakat memahami bahwa hutan yang terpelihara dengan baik akan menjadi jembatan bagi turunnya hujan sehingga mendukung USAha pertanian dan ketersediaan air bagi manusia dan makhluk hidup lainnya. Konsep Lende Ura mendorong masyarakat menghargai setiap komponen sumberdaya alam yang ada, serta berpengaruh baik secara langsung maupun tidak langsung terhadap proses terjadinya hujan. Karenanya, masyarakat tidak melakukan penebangan liar, menghindari kebakaran hutan dan lahan, memelihara daerah tangkapan air melalui budidaya pertanian campuran lahan kering serta memanfaatkan hasil hutan non kayu

High reward makes items easier to remember, but harder to bind to a new temporal context

Learning through reward is central to adaptive behavior. Indeed, items are remembered better if they are experienced while participants expect a reward, and people can deliberately prioritize memory for high- over low-valued items. Do memory advantages for high-valued items only emerge after deliberate prioritization in encoding? Or, do reward-based memory enhancements also apply to unrewarded memory tests and to implicit memory? First, we tested for a high-value memory advantage in unrewarded implicit- and explicit-tests (Experiment 1). Participants first learned high or low-reward values of 36 words, followed by unrewarded lexical decision and free-recall tests. High-value words were judged faster in lexical decision, and more often recalled in free recall. These two memory advantages for high-value words were negatively correlated suggesting at least two mechanisms by which reward value can influence later item-memorability. The ease with which the values were originally acquired explained the negative correlation: people who learned values earlier showed reward effects in implicit memory whereas people who learned values later showed reward effects in explicit memory. We then asked whether a high-value advantage would persist if trained items were linked to a new context (Experiments 2a and 2b). Following the same value training as in Experiment 1, participants learned lists composed of previously trained words mixed with new words, each followed by free recall. Thus, participants had to retrieve words only from the most recent list, irrespective of their values. High- and low-value words were recalled equally, but low-value words were recalled earlier than high-value words and high-value words were more often intruded (proactive interference). Thus, the high-value advantage holds for implicit- and explicit-memory, but comes with a side effect: High-value items are more difficult to relearn in a new context. Similar to emotional arousal, reward value can both enhance and impair memory

Eye fixations to figures in a four-choice situation with luminance balanced areas: Evaluating practice effects

Contingency analyses of eye movements may reveal variables that are relevant to the stimulus control of observing behavior. The present research tracked the eye movements of four adults exposed to a simultaneous discrimination among four stimuli, two two-dimensional (square and circle) and two three-dimensional (cube and cylinder) mono-chromatic figures with approximately equal luminance. On each discrimination trial, the stimuli were displayed in the four corners of a video monitor and participants chose among them by pressing corresponding keys. For two participants, choosing either cube or square (S+) was followed by the word “correct” and a 3-second inter-trial interval. Alternatively, choosing either cylinder or circle (S-) was followed by "incorrect" and a 30-second inter-trial interval. For the other two participants, contingencies were reversed. The position of the stimuli on the screen varied randomly across trials. The procedure continued for 80 trials. During these trials, discriminated choices were established. Despite the presence of both a two- and a three-dimensional S+ on each trial, responses to the three-dimensional S+ tended to prevail. Although general eye fixations tended to decrease as discrimination was established, subjects tended to observe S+ for longer durations than S-. Characteristics of the stimuli may interact with the contingencies of reinforcement in the stimulus control of observing behavior

ACG Clinical Guideline: Diagnosis and Management of Barrett’s Esophagus

Barrett's esophagus (BE) is among the most common conditions encountered by the gastroenterologist. In this document, the American College of Gastroenterology updates its guidance for the best practices in caring for these patients. These guidelines continue to endorse screening of high-risk patients for BE; however, routine screening is limited to men with reflux symptoms and multiple other risk factors. Acknowledging recent data on the low risk of malignant progression in patients with nondysplastic BE, endoscopic surveillance intervals are attenuated in this population; patients with nondysplastic BE should undergo endoscopic surveillance no more frequently than every 3-5 years. Neither routine use of biomarker panels nor advanced endoscopic imaging techniques (beyond high-definition endoscopy) is recommended at this time. Endoscopic ablative therapy is recommended for patients with BE and high-grade dysplasia, as well as T1a esophageal adenocarcinoma. Based on recent level 1 evidence, endoscopic ablative therapy is also recommended for patients with BE and low-grade dysplasia, although endoscopic surveillance continues to be an acceptable alternative. Given the relatively common recurrence of BE after ablation, we suggest postablation endoscopic surveillance intervals. Although many of the recommendations provided are based on weak evidence or expert opinion, this document provides a pragmatic framework for the care of the patient with BE