Improvement Torque Performances of Interior Permanent-Magnet Machines

Due to their excellent efficiency,power density and constant power speed region,interior permanent-magnet(IPM)machines are very suitable for electric vehicles(EVs).This paper proposed a new IPM rotor topology,which can offer high reluctance torque,wide constant power speed range and excellent overload capability.Besides,five rotor topologies with integral-slot distributed-windings IPM machines,including four existing IPM topologies and the proposed IPM topology,are designed optimally.Their characteristics,which include d-q axis inductances,saliency ratios,electromagnetic torques,corresponding torque ripples,back-electromotive forces(EMFs),overload capabilities and flux weakening performances are evaluated quantitatively.Finally,a three phase 48s8p hybrid rotor PM machine is built to verify the performances of the proposed IPM machine.This work provides some general concepts for machine developers who are willing to build IPM machines for high-performance EV applications.

The effect of soil moisture on the response by fungi and bacteria to nitrogen additions for N_(2)O production

In addition to bacteria,the contribution of fungi to nitrous oxide(N_(2)O)production has been recognized but the responses of these two broad and unrelated groups of microorganisms to global environmental changes,atmospheric nitrogen(N)deposition,and precipitation in terms of N_(2)O production are unclear.We studied how these two microbial-mediated N_(2)O production pathways responded to soil moisture conditions and to N addition in an N-limited temperate forest.Soils from a long-term N addition experiment in Changbai Mountain,northeastern China were incubated.Varied concentrations of cycloheximide and streptomycin,both inhibitors of fungal and bacterial activity,were used to determine the contributions of both to N_(2)O production in 66%,98%and 130%water-filled pore spaces(WFPS).The results showed that N_(2)O production decreased significantly with increasing cycloheximide concentration whereas streptomycin was only inhibiting N_(2)O emissions at 98%and 130%WFPS.The bacterial pathway of N_(2)O production in N-addition(Nadd)soil was significantly more dominant than that in untreated(Namb)soil.The difference in the fungal pathway of N_(2)O production between the soil with nitrogen addition and the untreated soil was not significant.Net N_(2)O emissions increased with increasing soil moisture,especially at 130%WFPS,a completely flooded condition.Bacteria dominated carbon dioxide(CO_(2))and N_(2)O emissions in Nadd soil and at 130%WFPS regardless of N status,while fungi dominated CO_(2)and N_(2)O emissions in soil without N addition at 66%and 98%WFPS.The results suggest that flooded soil is an important source of N_(2)O emissions and that bacteria might be better adapted to compete in fertile soils under anoxic conditions.

Neural Circuitry Involving Substance P in Male Sexual Behavior

Male sexual behavior is an innate social behavior crucial for reproduction[1].Previous studies have identified several brain regions crucial for the control of both sexual and aggressive behaviors in males.Yet,molecularly specified neural circuits that specifically control male sexual behavior remain elusive.Consistent with the inherently rewarding nature of sexual behavior,previous research has implicated the role of the dopamine system in regulating sexual desire[2].However,the interaction between reward and copulation at the circuit level remains largely unexplored.Besides,it is unclear if the associated neural pathways are specific in modulating sexual reward.

Rapid Eye Movement Sleep Consolidates Social Memory

Social memory is one of declarative memory which is essential for animals to exhibit appropriate social behaviors.Evidence suggests that the hippocampus,particularly the CA2 region,plays an important role in encoding and consolidating social memory[1].Rapid eye movement(REM)sleep has been suggested to contribute to social memory consolidation by up-regulating synaptic plasticity,local field potentials,and dendritic activity[2].

Lighting up Oxytocin Neurons to Nurture the Brain

The sensory system develops earlier than the systems responsible for higher brain functions such as language and cognition[1].Moreover,sensory experiences in early life are critical for the development of the brain.However,how sensory experiences shape brain development is an important yet unresolved question in neuroscience.Previous work has demonstrated that deprivation of sensory inputs in the early developmental stage causes synaptic dysfunction in the sensory cortex.Interestingly,it has been reported that oxytocin can restore the deficits caused by somatosensory deprivation in neonatal mice,suggesting that oxytocin may play a key role in sensory-mediated synaptogenesis[2].Vision is one of the most important sensory inputs during early development in mammalians including humans[1],but the neural mechanism underlying vision-mediated brain development is still largely unknown.

Sleeve Design of Permanent-magnet Machine for Low Rotor Losses

In this study,a novel rotor sleeve for permanent-magnet(PM)machines equipped with fractional-slot concentrated-windings(FSCW)is proposed.With the newly designed rotor sleeve,the rotor eddy-current(EC)losses are significantly reduced,and the torque density of the machine is improved.First,the rotor EC losses of a surface-mounted PM machine with the sleeve are analyzed.Meanwhile,the sleeve EC barriers and PM segmentation technologies for the suppression of the rotor EC losses are evaluated.Subsequently,an FSCW PM machine with the newly designed sleeve is proposed and optimized for a given set of specifications.Its electromagnetic and mechanical performances are evaluated by the finite element method(FEM).Finally,three assembling methods are presented and assessed comprehensively in terms of their merits and drawbacks.

A Standardized Protocol for the Induction of Specific Social Fear in Mice

Dear Editor,Social anxiety disorder(SAD)is one of the most common psychiatric disorders.It is characterized by intense and persistent fear of one or more social situations in which one is exposed to possible scrutiny by others[1].The lifetime prevalence of SAD ranges from 0.2%to 13%,with higher prevalence in high-income countries.Untreated SAD can last a lifetime and is often accompanied by impairments in social life,which severely compromises the quality of life.Furthermore,SAD is associated with a higher risk of other mental and physical disorders including depressive disor-ders,substance abuse disorders,general anxiety disorders,and cardiovascular diseases[2].

Pathway Matters: Prefrontal Control of Negative Emotions via Distinct Downstream Regions

The infralimbic cortex(IL)is a major subregion of the medial prefrontal cortex(mPFC)that is essential for many advanced brain functions including emotions.Mounting studies have unraveled a critical role of the IL in the processing of negative emotions such as fear and anxiety.However,these studies also generate controversial data regarding the precise functions of the IL in the regulation of either fear or anxiety.On one hand,pharmacological inactivation of the IL attenuates anxiety-like behaviors and consistently,pharmacological activation of the IL produces anxiety-like behaviors[1].