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Animals’ sensory systems adjust their responsiveness to environmental stimuli that vary greatly in their intensity. Here we report the neural mechanism of experience-dependent sensory adjustment, especially gain control, in the ASH nociceptive neurons in Caenorhabditis elegans. Using calcium imaging under gradual changes in stimulus intensity, we find that the ASH neurons of naive animals respond to concentration increases in a repulsive odor 2-nonanone regardless of the magnitude of the concentration increase. However, after preexposure to the odor, the ASH neurons exhibit significantly weak responses to a small gradual increase in odor concentration while their responses to a large gradual increase remain strong. Thus, preexposure changes the slope of stimulus–response relationships (i.e., gain control). Behavioral analysis suggests that this gain control contributes to the preexposure-dependent enhancement of odor avoidance behavior. Mathematical analysis reveals that the ASH response consists of fast and slow components, and that the fast component is specifically suppressed by preexposure. In addition, genetic analysis suggests that G protein signaling is required for the fast component. Thus, our integrative study demonstrates how prior experience dynamically modulates stimulus–response relationships in sensory neurons, eventually leading to adaptive modulation of behavior.

Although pyridinic-nitrogen (pyri-N) doped graphene is highly active for the oxygen reduction reaction (ORR) of fuel cells in alkaline media, the activity critically decreases under acidic conditions. We report on how to prevent the deactivation based on the mechanistic understanding that

Spiro compounds have been considered key scaffolds for pharmaceutical applications. Although many synthetic meth-ods exist for monospirocycles, fewer approaches are known for dispirocycles. Here, we report a highly cis-selective method for constructing a 5/6/5-dispirocyclic structure containing pyrrolidine and γ-lactam rings with various substit-uents from a series of N-arylpropiolamides. The high cis-selectivity would result from isomerization under thermody-namic control. Cis- and trans-diastereomers can be in equilibrium, favoring cis-adducts.

Imaging through scattering media is a longstanding issue in a wide range of applications, including biomedicine, security, and astronomy. Speckle-correlation imaging is promising for noninvasively seeing through scattering media by assuming shift invariance of the scattering process called the memory effect. However, the memory effect is known to be severely limited when the medium is thick. Under such a scattering condition, speckle-correlation imaging is not practical because the correlation of the speckle decays, reducing the field of view. To address this problem, we present a method for expanding the field of view of single-shot speckle-correlation imaging by extrapolating the correlation with a limited memory effect. We derive the imaging model under this scattering condition and its inversion for reconstructing the object. Our method simultaneously estimates both the object and the decay of the speckle correlation based on the gradient descent method. We numerically and experimentally demonstrate the proposed method by reconstructing point sources behind scattering media with a limited memory effect. In the demonstrations, our speckle-correlation imaging method with a minimal lensless optical setup realized a larger field of view compared with the conventional one. This study will make techniques for imaging through scattering media more practical in various fields.

Behavioral persistency reflects internal brain states, which are the foundations of multiple brain functions. However, experimental paradigms that enable genetic analyses of behavioral persistency and its associated brain functions have been limited. Here we report novel persistent behavioral responses caused by electric stimuli in the nematode Caenorhabditis elegans. When the animals on bacterial food are stimulated by alternating current, their movement speed suddenly increases more than 2-fold, which persists for minutes even after the electric stimulation is terminated. Genetic analyses reveal that multiple types of voltage-gated channels are required for the response, possibly as the sensors, and neuropeptide signaling regulates the duration of the persistent response. Additional behavioral analyses indicate that the animal’s response to electric shock is scalable and has a negative valence. These properties, along with persistence, have been recently regarded as essential features of emotion, suggesting that the animal’s response to electric shock may express a form of emotion, such as fear.

Upside down stomach (UDS) is a rare type of hiatal hernia. It is categorized by herniation of either the entire stomach or most of the gastric portion of the stomach into the posterior mediastinum. Acute UDS usually presents with abdominal and thoracic symptoms immediately after the stomach rotates, while chronic UDS often has either mild or no symptoms with the entire stomach rotated in the mediastinum. The first case was a 70-year-old female who was admitted with complaints of sudden vomiting and epigastric pain after eating. Computed tomography (CT) revealed UDS. Almost the entire stomach was twisted in the mediastinum, but the fornix was located in the abdominal cavity. After endoscopic reduction, the entire stomach was located in the mediastinum. Her symptoms disappeared and she was able to eat. The second case was another 70-year-old female with multiple hospitalizations due to frequent vomiting after eating. A review of previous CT scans showed a typical chronic UDS with the entire stomach located in the mediastinum. During her most current hospitalization, she was admitted with complaints of frequent vomiting and chest pain after overeating, and a CT showed UDS with only the fornix located in the abdominal cavity. Following hospitalization, the persistent vomiting disappeared and a CT scan at that point revealed that the fornix had returned to the mediastinum and she now had a normal UDS. These results indicate that chronic UDS caused acute symptoms due to "reverse incarceration" in the abdominal cavity through the diaphragmatic hiatus following eating. Chronic UDS is often either asymptomatic or only mildly symptomatic. However, these cases suggest that there is a mechanism whereby chronic UDS may cause acute UDS-like symptoms when the fornix becomes "reversely incarcerated" in the abdominal cavity following eating.

Praseodymium-containing double perovskites (Ba1-xSrx)2PrRuO6 were prepared. They crystallize in a monoclinic structure with space group P21/n in the range of 0 ≤ x ≤ 0.30. Magnetic susceptibility measurements show that all these (Ba1-xSrx)2PrRuO6 compounds order an antiferromagnetic transition at 95 ≤ T ≤ 117 K, and the Neel temperatures decrease with increasing Sr concentration (x value). Specific heat measurements and the magnetic entropy change for (Ba1-xSrx)2PrRuO6 also reveal the simultaneous magnetic ordering of Pr and Ru ions.