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Visual-LiDAR odometry and mapping (V-LOAM), which fuses complementary information of a camera and a LiDAR, is an attractive solution for accurate and robust pose estimation and mapping. However, existing systems could suffer nontrivial tracking errors arising from 1) association between 3D LiDAR points and sparse 2D features (i.e., 3D-2D depth association) and 2) obvious drifts in the vertical direction in the 6-degree of freedom (DOF) sweep-to-map optimization. In this paper, we present SDV-LOAM which incorporates a semi-direct visual odometry and an adaptive sweep-to-map LiDAR odometry to effectively avoid the above-mentioned errors and in turn achieve high tracking accuracy. The visual module of our SDV-LOAM directly extracts high-gradient pixels where 3D LiDAR points project on for tracking. To avoid the problem of large scale difference between matching frames in the VO, we design a novel point matching with propagation method to propagate points of a host frame to an intermediate keyframe which is closer to the current frame to reduce scale differences. To reduce the pose estimation drifts in the vertical direction, our LiDAR module employs an adaptive sweep-to-map optimization method which automatically choose to optimize 3 horizontal DOF or 6 full DOF pose according to the richness of geometric constraints in the vertical direction. In addition, we propose a novel sweep reconstruction method which can increase the input frequency of LiDAR point clouds to the same frequency as the camera images, and in turn yield a high frequency output of the LiDAR odometry in theory. Experimental results demonstrate that our SDV-LOAM ranks 8th on the KITTI odometry benchmark which outperforms most LiDAR/visual-LiDAR odometry systems. In addition, our visual module outperforms state-of-the-art visual odometry and our adaptive sweep-to-map optimization can improve the performance of several existing open-sourced LiDAR odometry systems. Moreover, we demonstrate our SDV-LOAM on a custom-built hardware platform in large-scale environments which achieves both a high accuracy and output frequency. We have released the source code of our SDV-LOAM for the development of the community.

Buzzing off If an ant or a bee ends up far from its colony (perhaps by artificial means such as a car or a plane), what will happen to it? The search turns successful when the bee or ant encounters a location from which it recognises the general direction to its home. Ants and honeybees remember their surroundings. [Extracted from the article]

Collateralized debt obligations, or CDOs, are structured vehicles that are similar to leveraged closed-end funds. Since their creation in the late 1980s, CDOs have evolved into three major classifications: cash [...]

Methyltransferases (MTases) play diverse roles in cellular processes. Aberrant methylation levels have been implicated in many diseases, indicating the need for the identification and development of small molecule inhibitors for each MTase. Specific inhibitors can serve as probes to investigate the function and validate therapeutic potential for the respective MTase. High-throughput screening (HTS) is a powerful method to identify initial hits for further optimization. Here, we report the development of a fluorescence-based MTase assay and compare this format with the recently developed MTase-Glo luminescence assay for application in HTS. Using protein N-terminal methyltransferase 1 (NTMT1) as a model system, we miniaturized to 1536-well quantitative HTS format. Through a pilot screen of 1428 pharmacologically active compounds and subsequent validation, we discovered that MTase-Glo produced lower false positive rates than the fluorescence-based MTase assay. Nevertheless, both assays displayed robust performance along with low reagent requirements and can potentially be employed as general HTS formats for the discovery of inhibitors for any MTase.

Gastric cancer is one of the most common gastrointestinal malignancies and is a lethal cancer. This study aimed to assess the factors affecting the survival and benefit of various therapeutic modalities in gastric adenocarcinoma (GAC) patients. Between March 2006 and October 2015, 121 GAC cases were identified by pathology and divided into groups I (surgery group; n = 41), II (IIa: 19 cases without treatment; IIb: 27 cases with palliative treatment), and III (combined surgery and postoperative chemotherapy; n = 34). Furthermore, the factors affecting early (12‐month) mortality and therapeutic outcomes between these groups were assessed over the study period. Patients who underwent treatment had longer survival than those who did not (groups I+IIb+III vs IIa, P< .001); group I provided the longest survival benefit among groups over the study period (Figure 2). Analyzing 12‐month mortality, significant differences were found in groups I vs IIa (P< .001), groups I vs IIb (P< .001), groups III vs IIa (P< .001), and groups III vs IIb (P< .001) in overall patients and in groups I vs IIa (P< .001), groups I vs IIb (P= .017), groups III vs IIa (P< .001), and groups III vs IIb (P< .001) in advanced‐stage patients (Table 2). Overall, the independent factors included advanced tumor stage (hazard ratio = 8.038, P= .007), absent treatment (hazard ratio = 14.009, P= .009), higher bilirubin (hazard ratio = 8.198, P= .047), and higher CEA (hazard ratio = 3.999, P= .030). Surgery provides better survival benefit, but palliative chemotherapy could also prolong unresectable GAC patients' survival. Factors of better liver preservation, lower carcinoembryonic antigen (CEA), and less aggressive tumor condition play crucial roles in predicting patients' survival.

Since abrasive gels with single direction motion are very difficulty to achieve the smooth surfaces in the complex holes finishing during abrasive flow machining (AFM), therefore, the helical cores were proposed here to create the multiple motions of abrasive gels to get the even surface of the complex holes in AFM. The results showed that helical core with 5 spiral grooves and narrow gap between the core tip and the hole could obtain the even surface and fine surface roughness after AMF.

Natural products and their derivatives continue to be wellsprings of nascent therapeutic potential. However, many laboratories have limited resources for biological evaluation, leaving their previously isolated or synthesized compounds largely or completely untested. To address this issue, the Canvass library of natural products was assembled, in collaboration with academic and industry researchers, for quantitative high-throughput screening (qHTS) across a diverse set of cell-based and biochemical assays. Characterization of the library in terms of physicochemical properties, structural diversity, and similarity to compounds in publicly available libraries indicates that the Canvass library contains many structural elements in common with approved drugs. The assay data generated were analyzed using a variety of quality control metrics, and the resultant assay profiles were explored using statistical methods, such as clustering and compound promiscuity analyses. Individual compounds were then sorted by structural class and activity profiles. Differential behavior based on these classifications, as well as noteworthy activities, are outlined herein. One such highlight is the activity of (−)-2(S)-cathafoline, which was found to stabilize calcium levels in the endoplasmic reticulum. The workflow described here illustrates a pilot effort to broadly survey the biological potential of natural products by utilizing the power of automation and high-throughput screening.

Membrane lipids, including sphingolipids and glycerol-phospholipids, are essential in maintaining the skin’s barrier function in mammals, but their composition in fish skin and their response to diets have not been evaluated. This study investigated the impacts of reducing dietary eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on membrane lipids in the skin of Atlantic salmon through a 26 week feeding regime supplying different levels (0–2.0% of dry mass) of EPA/DHA. Ceramide, glucosylceramide, sphingomyelin, sphingosine, and sphinganine in salmon skin were analyzed for the first time. Higher concentrations of glucosylceramide and sphingomyelin and higher ratios of glucosylceramide/ceramide and sphingomyelin/ceramide were detected in the deficient group, indicating interruptions in sphingolipidomics. Changes in the glycerol-phospholipid profile in fish skin caused by reducing dietary EPA and DHA were observed. There were no dietary impacts on epidermal thickness and mucus-cell density, but the changes in the phospholipid profile suggest that low dietary EPA and DHA may interrupt the barrier function of fish skin.

The characteristics of abrasive flow machining (AFM) make it a suitable method to polish complex holes and curved surface. Anyway, the traditional abrasive flowing machining (AFM) methods have difficulty achieving uniform roughness of radial distribution in polishing of complex holes due to the non-uniform abrasive forces. The abrasive media are the key elements that dominate the polishing behavior in AFM process. However, commercial abrasive media are very expensive, and not every user can afford the prices. Therefore, lower-cost and effective abrasive media are developed to improve the surface roughness of the WEDM workpieces in this research. Besides, the application of abrasive gels with a helical passageway is proposed to create a multiple motion of abrasive medium and to obtain the even surface of the complex holes in AFM process.

Poly(ADP-ribose) polymerase inhibitors (PARPis) have changed the treatment paradigm in breast cancer gene (BRCA)–mutant high-grade serous ovarian carcinoma (HGSC). However, most patients eventually develop resistance to PARPis, highlighting an unmet need for improved therapeutic strategies. Using high-throughput drug screens, we identified ataxia telangiectasia and rad3-related protein/checkpoint kinase 1 (CHK1) pathway inhibitors as cytotoxic and further validated the activity of the CHK1 inhibitor (CHK1i) prexasertib in PARPi-sensitive and -resistant BRCA-mutant HGSC cells and xenograft mouse models. CHK1i monotherapy induced DNA damage, apoptosis, and tumor size reduction. We then conducted a phase 2 study (NCT02203513) of prexasertib in patients with BRCA-mutant HGSC. The treatment was well tolerated but yielded an objective response rate of 6% (1 of 17; one partial response) in patients with previous PARPi treatment. Exploratory biomarker analyses revealed that replication stress and fork stabilization were associated with clinical benefit to CHK1i. In particular, overexpression of Bloom syndrome RecQ helicase (BLM) and cyclin E1 (CCNE1) overexpression or copy number gain/amplification were seen in patients who derived durable benefit from CHK1i. BRCAreversion mutation in previously PARPi-treated BRCA-mutant patients was not associated with resistance to CHK1i. Our findings suggest that replication fork–related genes should be further evaluated as biomarkers for CHK1i sensitivity in patients with BRCA-mutant HGSC.

ABSTRACT:This paper intends to study the tonal variation between tone 3a (i.e. Yinqu阴去) and 2b (i.e. Yangshang阳上) as observed in modern Hong Kong Cantonese. Two social variables will be involved: age and gender. In the light of apparent time hypothesis, the findings help to determine whether such a variation is a result of an on-going sound change. The results reveal that there are two on-going tone changes in opposite directions, namely, 3a 2b and 2b 3a, and so far the former seems more forceful than the latter. The sound changes are carried out by lexical diffusion, and the unit of diffusion is more likely to be disyllabic and other polysyllabic compound words rather than monosyllabic morphemes. The gender variable, on the other hand, is found significant only in 2b 3a. 提要:本文旨在探讨现代香港粤语所出现的阴去(3a 调)与阳上(2b 调)声调交替的现象。本文将考察以下两个因素的影响：年龄和性别。基于显象时间假设，研究结果有助判定这种语音交替是否正在进行中的音变。结果显示，有两个相反方向的音变正在发生，即 3a 2b 和 2b 3a，迄今前者的力量较大。另外，两者皆以词汇扩散的方式进行，但扩散的单位并非单音节的语素，而是双音节乃至多音节的合成词。至于性别此一因素，则只于 3b 3a 发现有显著作用。

Intrahepatic cholangiocellular carcinoma (ICC) is an uncommon but lethal cancer. The aim of this study is to assess the factors affecting the survival of ICC patients and to evaluate the benefit of these factors when various therapeutic modalities are used.

Pseudoachalasia, or secondary achalasia, caused by neoplasms is a rare entity. We describe a case of pseudoachalasia in an 80-year-old woman who presented with a 2-month history of progressive dysphagia and postprandial vomiting. An esophagogram demonstrated a markedly dilated esophagus with a typical “bird-beak” appearance of the gastroesophageal junction, indicative of achalasia. However, esophageal manometric study disclosed normal peristalsis of the esophagus, not suggestive of a typical feature of achalasia. Abdominal computed tomography scan demonstrated a hypovascular tumor in the left lobe of the liver, extending to the gastroesophageal junction and proximal lesser curve of the stomach. The patient underwent a palliative gastrostomy with a liver biopsy. Finally, cholangiocarcinoma was diagnosed based on the pathological findings. Despite its rarity, clinicians should be aware of this finding as a potential cause of dysphagia in elderly patients.

Methods to identify the bioactive diversity within natural product extracts (NPEs) continue to evolve. NPEs constitute complex mixtures of chemical substances varying in structure, composition, and abundance. NPEs can therefore be challenging to evaluate efficiently with high-throughput screening approaches designed to test pure substances. Here we facilitate the rapid identification and prioritization of antimalarial NPEs using a pharmacologically driven, quantitative high-throughput-screening (qHTS) paradigm. In qHTS each NPE is tested across a concentration range from which sigmoidal response, efficacy, and apparent EC50s can be used to rank order NPEs for subsequent organism reculture, extraction, and fractionation. Using an NPE library derived from diverse marine microorganisms we observed potent antimalarial activity from two Streptomycessp. extracts identified from thousands tested using qHTS. Seven compounds were isolated from two phylogenetically related Streptomycesspecies: Streptomyces ballenaensiscollected from Costa Rica and Streptomyces bangulaensiscollected from Papua New Guinea. Among them we identified actinoramides A and B, belonging to the unusually elaborated nonproteinogenic amino-acid-containing tetrapeptide series of natural products. In addition, we characterized a series of new compounds, including an artifact, 25-epi-actinoramide A, and actinoramides D, E, and F, which are closely related biosynthetic congeners of the previously reported metabolites.

The machining method of effortless, low–cost and high effective polishing called abrasive flow machining (AFM) is developed to obtain high quality products for surface polishing. However, a smoother surface is not easily created after polishing since one–way motion of abrasive media in traditional AFM. Hence, this study designs a novel helical core to perform multiple flowing paths of an abrasive medium to improve the surface roughness (SR). In this investigation, Taguchi method is adopted to find out the optimal parameters of a helical core first; then, hole with or without a helical core is studied to verify the polishing effect of a helical passageway. The results represent an excellent solution that the helical passageway performed better in reducing roughness improvement ratio (RIR) by approximately 77% compared to RIR near 60% for the original circular passageway. Moreover, this study also demonstrates the efficiency of the helical passageway in surface roughness uniformity based on the percentage of improvement ratio around 70%.

Diverse invertebrate species have been used for studies of learning and comparative cognition. Although we have gained invaluable information from this, in this study we argue that our approach to comparative learning research is rather deficient. Generally invertebrate learning research has focused mainly on arthropods, and most of that within the Hymenoptera and Diptera. Any true comparative analysis of the distribution of comparative cognitive abilities across phyla is hampered by this bias, and more fundamentally by a reporting bias toward positive results. To understand the limits of learning and cognition for a species, knowing what animals cannot do is at least as important as reporting what they can. Finally, much more effort needs to be focused on the neurobiological analysis of different types of learning to truly understand the differences and similarities of learning types. In this review, we first give a brief overview of the various forms of learning in invertebrates. We also suggest areas where further study is needed for a more comparative understanding of learning. Finally, using what is known of learning in honeybees and the well‐studied honeybee brain, we present a model of how various complex forms of learning may be accounted for with the same neural circuitry required for so‐called simple learning types. At the neurobiological level, different learning phenomena are unlikely to be independent, and without considering this it is very difficult to correctly interpret the phylogenetic distribution of learning and cognitive abilities. WIREs Cogn Sci2013, 4:561–582. doi: 10.1002/wcs.1248

Conventional AFM have difficulty achieving uniform roughness of an axial distribution in circular hole polishing due to limited unitary axial motion of abrasive media. Therefore, this work develops mechanism designs for different passageways to obtain multiple flowing paths of an abrasive medium, whose flowing behavior enhances polishing effectiveness by increasing the abrasive surface area and radial shear forces. The motion of the abrasive medium is studied by utilizing the design of the mold cores, which mold shapes include the circular passageway and helical passageway. The optimum design of the different passageways is then verified using CFD-ACE+ numerical software. Analytical results indicate that the optimum design is the mechanism with a passageway of six helices. Furthermore, surface roughness measurements demonstrate the increase in uniformity and the roughness improvement rate (RIR). Experimental results for surface roughness indicate that roughness deviation of six helices passageway of approximately 0.1001 m Ra is significantly better than those on a circular passageway of around 0.1760 m Ra. Additionally, the six helices passageway is also superior to circular passageway in reducing roughness improvement rate (RIR) by roughly 85% compared with RIR 75% for the circular passageway.

Abrasive flow machining (AFM) is a simple and efficient method to remove recasting layers making by wire electrical discharge machining (WEDM). However, conventional AFM methods have difficulty achieving uniform roughness of an axial distribution in circular hole polishing due to limited unitary axial motion of abrasive media. Therefore, this work develops mechanism designs for different passageways to obtain multiple flowing paths of abrasive medium, whose flowing behavior enhances polishing effectiveness by increasing the abrasive surface area and radial shear forces. The motion of the abrasive medium is studied by utilizing different mold cores, which mold shapes include the circular, hollow and helical passageway. The optimum design of the passageways is then verified using CFD-ACE+ software, numerical results indicate that passageway with six helices performed better in the uniform surface roughness than others’ do. Experimental results show that roughness deviation of six helices passageway of approximately 0.100 m Ra is significantly better than those on a circular passageway of around 0.1760 m Ra. Additionally, the six helices passageway is also superior to circular passageway in reducing roughness improvement rate (RIR) by roughly 87% compared with RIR 67.7% for the circular passageway.

Generally, impact and shock to portable electronic products can cause significant functional and physical damage in the form of internal component failure or package-to-board interconnection breakage. Therefore, this paper provides a dynamic simulation of shock impact to investigate the internal stress and strains of a printed circuit board (PCB) with ball grid array (BGA) chipset. The tin balls will be simulated with a minimum element size as 0.0536 mm in LS-DYNA finite element software. The corresponding strains of dynamic analysis on PCB board will be compared with those of the experimental measurements using the strain gauge. Finally, the model established has values of peak strain and impact duration close to those measured in the actual shock test. The comparison results of the experimental and numerical strain show that the smallest difference is 0.70%. Furthermore, we also investigate the signal curves of experimental error source on the accelerometer and strain gauge. The measurement results show that the capabilities of the repetition and stability both the input signals and output signals are excellent. This result provides researchers in relevant fields with an excellent example and model for further study of PCB with BGA chipsets.

The debris re-adhering on the machining surface will affect the workpiece precision in EDM; therefore, the main purpose of this research is to study the re-sticky phenomenon of the powder metallurgy (PMM) in EDM. PMM with different melting points from 1450oC to 3410oC were used as EDM materials, the copper and the tungsten were chosen as the electrodes. The polarity in EDM was depended on the pole of the electrode. For observing the re-sticky position of the debris, the electrode was set no rotation or with 200 rpm rotational speed in EDM. The results showed that the melting point of PMM did not exceed 3000oC (PMM did not contain tungsten); the debris of PMM would not re-stick on the working surface no matter what polarity was used in EDM. However, only negative polarity can cause the re-adhesive effect when the melting point of PMM exceeded 3000oC. The debris would re-stick on any machining position when the electrode was not rotated in EDM. However, the debris would adhere on the central of the working area with 200 rpm rotational speed of the electrode.

Objective: To describe a case of fosinopril-induced severe cholestatic jaundice successfully treated with plasma exchange.Case Summary: A 78-year-old Taiwanese male presented with yellowish skin and generalized itching one month after starting fosinopril 10 mg once a day. Other drugs taken by the patient were excluded as the probable cause of jaundice. Diagnostic modalities, including abdominal ultrasound, computed tomography, and endoscopic retrograde cholangiopancreatography, revealed no evidence of biliary tract obstruction or intraabdominal tumor. According to the Council for International Organizations of Medical Science (CIOMS) scale, fosinopril was a highly probable cause of the patient's jaundice. Liver biopsy showed cholestasis without bile duct damage. Based on results of the CIOMS scale assessment and pathological characteristics of the liver, the diagnosis was highly probable that fosinopril had induced cholestatic jaundice in our patient. During hospitalization, the patient developed severe jaundice and liver failure, despite conservative treatment and withdrawal of fosinopril. He underwent a 5-day course of plasma exchange therapy, and the serum bilirubin level declined rapidly after treatment. His liver function returned to normal 2 months after treatment.Discussion: Angiotensin-converting enzyme (ACE) inhibitor–induced hepatotoxicity is rare and only a few cases, with most involving captopril, have been reported in the English-language literature. Hepatotoxicity caused by fosinopril is extremely rare. Most ACE inhibitor–induced hepatotoxicity is mild and transient, but it can be fatal. Although orthotopic liver transplantation (OLT) is the standard method for treating drug-induced liver failure, plasma exchange therapy is an alternative therapeutic method or a bridge to OLT for treating liver failure.Conclusions: Plasma exchange therapy may play a valuable role in the treatment of fosinopril-induced cholestatic jaundice and liver failure. This intervention can be considered for temporary liver support until recovery or OLT.

Abstract: There is evidence, beginning with Cheng (1986), that mobile animals may use the geometry of surrounding areas to reorient following disorientation. Gallistel (1990) proposed that geometry is used to compute the major or minor axes of space and suggested that such information might form an encapsulated cognitive module. Research reviewed here, conducted on a wide variety of species since the initial discovery of the use of geometry and the formulation of the modularity claim, has supported some aspects of the approach, while casting doubt on others. Three possible processing models are presented that vary in the way in which (and the extent to which) they instantiate the modularity claim. The extant data do not permit us to discriminate among them. We propose a modified concept of modularity for which an empirical program of research is more tractable.

Abstract: Self-control means choosing a large delayed reward over a small immediate reward; impulsiveness is its opposite. The metabolic hypothesis states that the amount of self-control across species correlates negatively with metabolic rate (Tobin & Logue, 1994). Foraging honeybees have high metabolic rates; the metabolic hypothesis would predict little self-control in bees. But foraging bees work for the longterm good of their hive, conditions that seem to require self-control. In three experiments, we gave bees the choice between (1) a sweeter delayed reward and a less sweet immediate reward and (2) a large delayed reward and a small immediate reward. Bees showed much self-control, inconsistent with the metabolic hypothesis.

An overview of mechanistic and functional accounts of stimulus generalisation is given. Mechanistic accounts rely on the process of spreading activation across units representing stimuli. Different models implement the spread in different ways, ranging from diffusion to connectionist networks. A functional account proposed by Shepard analyses the probabilistic structure of the world for invariants. A universal law based on one such invariant claims that under a suitable scaling of the stimulus dimension, generalisation gradients should be approximately exponential in shape. Data from both vertebrates and invertebrates so far uphold Shepard's law. Some data on spatial generalisation in honeybees are presented to illustrate how Shepard's law can be used to determine the metric for combining discrepancies in different stimulus dimensions. The phenomenon of peak shift is discussed. Comments on mechanistic and functional approaches to generalisation are given.

Animals use many different mechanisms to navigate in space. The characteristics of the mechanism employed are usually well-suited to the demands of each particular navigational problem. For example, desert ants navigating in a relatively featureless environment use path integration, birds homing or migrating over long distances use compasses of various sorts, salmon returning to their natal stream home on olfactory cues. The study of navigation requires the study of many different taxa confronting different problems. One interesting case involves scatter-hoarding species that use memory to relocate their hidden food. Such animals face the problem of remembering many locations simultaneously. Clark's nutcrackers (Nucifraga columbiana) are an excellent example, and this paper considers their possible use of multiple bearings from landmarks.

Gastrodia elataBl. (GE) is a traditional Chinese herb that is commonly used in Chinese communities to treat convulsive disorders such as epilepsy. The purpose of the present study was to determine the anticonvulsive and free radical activities of GE in rats. In vitrostudies were conducted by using brain tissue from 6 male Sprague-Dawley (SD) rats treated with 120 μg/ml of kainic acid (KA), with or without the addition of various concentrations of GE. In vivostudies were conducted in a total of 30 male SD rats divided into 5 groups of 6 rats which were treated as follows: 1) the normal group received an intraperitoneal injection (i.p.) of PBS (Phosphate buffer saline, 1 ml/kg); 2) the control group received KA (12 mg/kg) i.p.; 3) the GE 1.0 group received oral administration of GE 1.0 g/kg 30 min prior to KA administration; 4) the GE 0.5 group reveived oral administration of GE 0.5 g/kg 30 min prior to KA administration; 5) the PH group reveived oral administration of phenytoin 20 mg/kg 30 min prior to KA administration. Seizures were verified by behavioral observations, electroencephalograph (EEG) and electromyography (EMG). Lipid peroxide levels in the rat brain, luminol chemiluminescence (CL) and lucigenin-CL in the peripheral blood were measured simultaneously after behavioral observations. The results indicate that GE administration significantly reduced KA-induced lipid peroxide levels in vitro. Oral administration of GE 1.0 g/kg and phenytoin 20 mg/kg significantly reduced counts of wet dog shakes (WSS), paw tremor (PT) and facial myoclonia (FM) in KA-treated rats. In addition, oral administration of GE 1.0 g/kg significantly delayed the onset of WDS, from 30 min in the control group to 46 min in the 0.5 g/kg group, and 63 min in the GE 1.0 g/kg group. A significantly reduced level of lipid peroxides in the rat brain was found in the GE 1.0 g/kg, 0.5 g/kg, and phenytoin 20 mg/kg groups. The GE 1.0 g/kg group showed significant reduction of luminol-CL and lucigenin-CL counts in the peripheral blood compared to the control group. The results of the present study demonstrate that GE has anticonvulsive and free radical scavenging activities. Further studies are needed to determine the clinical effectiveness of GE as an anticonvulsant in humans.

The central Australian ant Melophorus bagoti is the most thermophilic ant in Australia and forages solitarily in the summer months during the hottest period of the day. For successful navigation, desert ants of many species are known to integrate a path and learn landmark cues around the nest. Ants perform a series of exploratory walks around the nest before their first foraging trip, during which they are presumed to learn about their landmark panorama. Here, we studied 15 naive M. bagoti ants transitioning from indoor work to foraging outside the nest. In 3–4 consecutive days, they performed 3–7 exploratory walks before heading off to forage. Naive ants increased the area of exploration around the nest and the duration of trips over successive learning walks. In their first foraging walk, the majority of the ants followed a direction explored on their last learning walk. During learning walks, the ants stopped and performed stereotypical orientation behaviours called pirouettes. They performed complete body rotations with stopping phases as well as small circular walks without stops known as voltes. After just one learning walk, these desert ants could head in the home direction from locations 2 m from the nest, although not from locations 4 m from the nest. These results suggest gradual learning of the visual landmark panorama around the foragers’ nest. Our observations show that M. bagoti exhibit similar characteristics in their learning walks to other desert ants of the genera Ocymyrmex and Cataglyphis.

Abstract: Honeybees were trained to find sugar water in the middle of an array of two landmarks of different colours. Unrewarded tests compared searching on the training array with searching on rotated arrays. On rotated tests, a system using the angles between landmarks would continue to search in the middle. A system using vectors to individual elements would search at locations outside the rotated array at which the distances and compass directions to a subset of landmarks matched. Results indicated that bees used both elements and interlandmark angles, but they relied most on one favourite landmark element. Results support the template model of landmark use in honeybees, with the minor parametric modification that weights given to different elements may be unequal.

Pigeons obtained food by pecking at an unmarked target location on a video screen equipped with a touch-sensitive frame. The target area was located near the top edge of the screen in Experiment 1 and near the left edge of the screen in Experiment 2. On baseline trials, a graphic landmark was located below and left of the target (Experiment 1) or below and right of the target (Experiment 2). In both experiments, baseline search distributions showed a single peak and were roughly symmetrical about the target area in both horizontal and vertical dimensions. On occasional test trials, the landmark was shifted horizontally, vertically, or diagonally by 1.5 cm or 3 cm. In both experiments, landmark shifts in the dimension parallel to the nearest edge produced systematic shifts in the peak place of search. Landmark shifts in the dimension perpendicular to the nearest edge produced inconsistent (Experiment 1) or relatively small (Experiment 2) shifts in peak place. The magnitude of the behavioral shift was always less than the magnitude of the landmark shift and was not consistently greater when the landmark was shifted by 3 cm than when it was shifted by 1.5 cm. These results demonstrated that pigeons can accurately locate an unmarked target area in a two-dimensional vertical arena and that their use of landmarks for spatial localization is similar in several respects to that found in open-field spatial search tasks.

The peak procedure was used in two experiments. Pigeons in the penalty group in Experiment 1 were rewarded with food in the first phase for the first peck after 12.5 sec had elapsed since the onset of a keylight. In the second phase, reward was withheld if the pigeons pecked within 6.25 sec after keylight onset. Responses in time were tabulated on occasional unrewarded tests in which the keylight was left on for 37.5 sec. Under the penalty contingencies, the response distribution in time remained nearly symmetric about the peak, while the spread of the distribution narrowed, and the time of peak responding came slightly earlier. The yoke group underwent a schedule of rewards similar to that for the penalty group, but without the penalty contingencies. Their response distributions remained similar throughout. The results of Experiment 1 were replicated in Experiment 2, which showed further that the changes due to the penalty contingencies did not generalize to the use of another key on which the penalty contingencies were not in effect. The narrower spread under the penalty contingencies is explained in terms of a change in threshold for when to start responding, and more weight being given to timing versus responding in the presence of the signal per se. No explanation was found for the change in the time of peak responding.

Myopic crescent, refractive error and axial length were previously investigated in Hong Kong Chinese subjects. The myopic crescent was found to correlate with axial length and myopic refraction. In this study, three groups of Hong Kong Chinese with different degrees of myopia were assessed for optic disc ovalness, refractive error and axial length. The axial length was significantly correlated with the degree of myopia, indicating that the myopia was axial in nature. The regression line shows that 0.44 mm of axial elongation would give about one dioptre of increase in myopia. The elliptical ratio of the optic disc was defined as the maximal disc diameter divided by the minimal disc diameter. All three groups showed an oval disc with vertical axis greater and an increased ovalness for the high myopic group with an elliptical ratio from 1.11 in low myopia to 1.29 in high myopia. There is a small amount (about four degrees) of temporal rotation of this vertical oval orientation, which is independent of the amount of myopia. This result shows an association between axial elongation of the globe and optic disc ovalness, in addition to the previously described temporal myopic crescent. Therefore, in myopic subjects, a vertically oval disc may be associated with a myopic refraction rather than glaucoma.

Our question was: Does the alleged universality of Brown's Invariant Norm of Address (1965) extend to Chinese usage? Or, does the alleged universal relationship between social power and intimacy and between inequality and equality hold for Chinese social structure? To answer these questions, we developed three quantitative indices which measure the degrees of reciprocity, solidarity, and inequality in dyadic address exchanges. The indices permit the precise comparison of empirical results with theoretical predictions and of address usage across languages. Seventy Chinese speakers forming a diverse sample reported actual address usage received from and sent to 27 interactants. The results revealed the structure of address usage among Chinese speakers and provided unequivocal support for Brown's prediction such that we may confidently add Chinese to the series of languages which jointly support the claim for the universality of the Invariant Norm. The relationship between studies in the semantics of social structure and the emerging alternative social-psychological strategy of ethogenyis noted.

Pigeons (Columba livia) were trained to find hidden food in a sunken well within a square box. After learning the location, they were tested occasionally with the well and food absent. The resulting search distributions were symmetric about the peak, implying a linear scale of measurement for distance. The spread of the distribution was a constant proportion of the distance to the nearest landmark, supporting Weber's Law. As well, in one test in which a landmark was shifted in a diagonal direction, the pigeons shifted their peak place of search both in the direction of landmark shift and in the direction orthogonal to the direction of landmark shift. This contradicted a pattern found earlier: For landmark shifts along the principal axes of the square box, pigeons only shifted their peak place of search in the direction of landmark shift, not in the orthogonal direction. The vector sum model, which predicts shifts of the peak place of search only in the direction of landmark shift, is disconfirmed and must be revised.

1.Three pigeons (Columba livid) were trained to find hidden food in a sunken well (3.3 cm in diameter) at a constant place within an (160 cm×160 cm) experimental box (Fig. 1). After learning the location, the animals were tested occasionally with the well and food absent. Landmarks in the experimental box might be transformed on such tests.2.Changing the height or width of a nearby landmark had no systematic influence on the position of peak search. Translating a nearby landmark, however, led to a shift in peak search position. All three birds then searched most somewhere between the original goal location, as defined by the unmoved landmarks, and the goal location as defined by the shifted landmark. Within a limited range of landmark shift, the peak shift as a function of landmark shift is linear (Fig. 3).3.To explain the data (Fig. 7), the pigeon records at the location of the goal the algebraic vectors from a number of landmarks to the goal. These vectors have both a direction and a distance component. When searching for the goal again in the experimental box, it computes independently for each landmark a navigation vector. This is arrived at by vector-adding the algebraic vector from the bird's current position to the landmark in question, supplied by perception, to the corresponding landmark-goal vector in its record. The pigeon moves in the direction and distance specified by a weighted average of the independently calculated navigation vectors. For positive vector weights, vector geometry guarantees that the bird would search somewhere between the original goal and the goal according to the shifted landmark. The extent to which it shifts toward the shifted goal reflects the vector weight given to the shifted landmark.

A cw CO_2 laser has been developed in which the active medium is formed by a discharge between coaxial electrodes. The laser gain and saturation properties have been studied as functions of the various device parameters. Over-all efficiency is about the same as for a conventional longitudinal discharge laser, and advantages of the coaxial geometry include low voltage operation, rapid cooling, and rugged construction.

No relevant conflicts of interest to declare.