From the Cover: Algorithmic design of self-assembling structures

We study inverse statistical mechanics: how can one design a potential function so as to produce a specified ground state? In this article, we show that unexpectedly simple potential functions suffice for certain symmetrical configurations, and we apply techniques from coding and information theory to provide mathematical proof that the ground state has been achieved. These potential functions are required to be decreasing and convex, which rules out the use of potential wells. Furthermore, we give an algorithm for constructing a potential function with a desired ground state.     

大面积新近软弱吹填土施工场地的处理方法

通过对某大型工程建筑场地分布的浅部新近吹填土的土质情况及桩机施工场地处理方法的分析，介绍了相应的施工场地处理经验，供勘察设计等有关人员遇到类似情况时作参考。     

Functional Organization of Area V2 in the Alert Macaque

We studied the relation between anatomical structure and functional properties of cells in area V2 of the macaque. Visual function was assessed in the alert animal during fixation of gaze. Recording sites were reconstructed with respect to cortical lamination and the cytochrome oxidase pattern. We measured orientation and direction selectivity, end-stopping, sensitivity to binocular disparity and ocular dominance, and determined more complex functions like sensitivity to anomalous contours and lines defined by coherent motion. Orientation selectivity was found in all parts of area V2, with high frequencies in the pale and thick stripes of the cytochrome oxidase pattern, and with lower frequency in the thin stripes. Representations of anomalous contours were found in the pale and thick stripes with similar frequencies, but generally not in the thin stripes, which have been thought to process colour. Lines defined by coherent motion were most frequently represented in the thick stripes; they were less frequent in the pale stripes, and (as with anomalous contours) were not found in the thin stripes. Sensitivity to binocular disparity was found in all types of stripes, but more frequently in the thick stripes, where the exclusively binocular neurons were also concentrated. By contrast, no segregation was found for direction selectivity and end-stopping. All neuronal properties were distributed evenly across cortical laminae. We conclude that mechanisms for figure–ground segregation involve the pale and the thick stripes of the cytochrome oxidase pattern, perhaps with greater emphasis on 'shape from motion'and 'stereoscopic depth'in the thick stripes, while more elementary neuronal properties are distributed almost evenly across the stripe pattern.     

几种特因作用下黄鼠心电图的变化

为研究航天环境因素对冬眠动物的影响，用成年黄鼠在５组特因条件下进行了１３只次实验。初步观察了心电图的变化，被动性异位节律、传导及ＳＴ－Ｔ异常等。特殊因素解除后心电图恢复正常。产生机理属于反射性和中枢性。ＥＣＧ的变化是功能性的，非病理性的。     

An Apparatus for Recording Defensive Responses to Tactile Stimulation in the Ground Snail

We describe here an original working experimental apparatus for non-invasive objective recording of the magnitudes of defensive responses to tactile stimulation in the ground snail. The apparatus includes a tracking device that ensures that the snail's position relative to a light and photodiode remains constant as it ascends a cylinder rotating about a horizontal axis. The device providing tactile stimulation is based on a loudspeaker circuit and provides blows of dosed energy. The snail responds to the tactile stimulation by retracting the antennae, head, and foot, which decreases the area of its shadow; this is recorded by a photodiode.     

DNA damage in peripheral blood lymphocytes of individuals residing near a wastewater drain and using underground water resources

Mahal is a linear village settlement situated about 0.5 km from an open waste-water drain, the Tung Dhab drain, which carries effluents from local industrial sites. Villagers generally have a low-to-middle socio-economic status and use ground water or a combination of ground water and tap water for drinking and for their other daily activities. The land in and around Mahal is used for agriculture and is irrigated by water from the Tung Dhab. The drain water contains heavy metals, and there is a possibility that these and other contaminants may reach the ground water table of Mahal and thereby compromise the health of the residents. The comet assay was performed on peripheral blood lymphocytes from Mahal villagers and revealed statistically significant increases in DNA damage as compared to a control group that does not use ground water. DNA damage was also significantly related to the age of the villagers and to the length of residence in the village. In the absence of other environmental exposures, it is concluded that the elevated DNA damage in the villagers is a consequence of continuous utilization of contaminated ground water.     

Unilateral dorsal column and rubrospinal tract injuries affect overground locomotion in the unrestrained rat

The purpose of this study was to determine the importance of the rubrospinal pathway and the ascending components of the dorsal column for overground locomotion in adult, unrestrained rats. The dorsal column (excluding the corticospinal tract), the rubrospinal tract or both were damaged unilaterally in rats at the level of the upper cervical spinal cord. Behavioural analysis consisted of skilled locomotion (an evaluation of footslips during ladder walking), a paw usage task and the assessment of ground reaction forces during unrestrained locomotion. All lesioned animals used the forepaw ipsilateral to the lesions less while rearing. Animals with dorsal column injuries used the forelimb contralateral to the spinal injury significantly more while rearing compared with uninjured animals. All lesioned animals produced more footfalls while crossing the ladder compared with uninjured animals. All injuries, regardless of the pathway affected, resulted in significant alterations in body weight support and reduced braking forces from the forelimb ipsilateral to the injury during overground locomotion. Animals typically bore less weight on the hindlimb ipsilateral to the lesion compared with the hindlimb contralateral to the spinal injury. Taken together with previously published work, our data indicate that the rubrospinal and dorsal column pathways are important for forelimb support while rearing and for skilled locomotion. Additionally, the ascending dorsal column pathways and the rubrospinal tract play a role during flat surface overground locomotion and combined damage to these pathways does not alter the acquired gait.     

泽兰有效部分对血小板聚集和血栓形成的影响

目的 研究泽兰有效部分L．F04：对血小板聚集和血栓形成的影响，探讨其活血化瘀作用机制。方法用高分子右旋糖酐静脉推注造成大鼠血瘀证模型，观察泽兰L.F04对二磷酸腺苷(ADP)诱导的大鼠体内血小板聚集以及体内动静脉旁路血栓、体外旋转环内血栓形成的影响。结果 L．F04 0．408，0．204g／kg对模型组大鼠ADP诱导的体内血小板最大聚集率明显增加皆有显著的抑制。且呈剂量依赖关系；与对照组相比，血瘀模型大鼠体外血栓质量明显增加，长度仅有增加趋势，L．F04高、低剂量(0．408，0．204g／kg)皆有抗血栓形成作用，L．F04高剂量对血栓干质量、湿质量的减轻尤为明显；L．F04高、低剂量对实验性动静脉旁路血栓形成均有明显的抑制作用，抑制率分别为27．41％，27．14％。结论泽兰L．F04可显著抑制血小板聚集及体内、外血栓形成。     

Ground glass hepatocytes contain pre-S mutants and represent preneoplastic lesions in chronic hepatitis B virus infection

The discovery of "ground glass" hepatocytes (GGH) that contain hepatitis B virus (HBV) surface antigens by Hadziyannis and Popper in 1973 represents a historical landmark in the pathology of chronic HBV infection. Different types of GGH have been correlated to the expression patterns of surface/core antigens and the stages of virus replication. The original two types (designated types I & II) of GGH were found to contain specific pre-S mutants with deletions over either pre-S1 or pre-S2 regions, respectively. Type II GGH consistently harbor pre-S2 deletion mutants, which can escape from immune attack and grow preferentially to form clusters. Both types of pre-S mutants can induce endoplasmic reticulum (ER) stress and oxidative DNA damage. The pre-S2 mutants, albeit inducing a weaker level of ER stress signals, could additionally initiate ER stress-independent retinoblastoma/adenovirus E2 promoter binding factor/cyclin A signaling through their interaction with c-Jun activation domain binding protein 1 to degrade p27, illustrating the growth advantage of type II GGH. The combined effects of genomic instability and the proliferation of hepatocytes harboring pre-S mutants could potentially lead to hepatocarcinogenesis over the decades of chronic HBV infection. The presence of pre-S mutants in sera was reported to carry a high risk of developing hepatocellular carcinoma (HCC). Furthermore, transgenic mice harboring pre-S2 mutant plasmids have been shown to develop a dysplastic change of hepatocytes and HCC. Therefore, in addition to being a histological marker of chronic HBV infection, GGH, particularly type II GGH, may represent the preneoplastic lesions of HBV-related HCC.     

The association of cortisol levels with leukocyte distribution is disrupted in the metabolic syndrome

BackgroundLeukocyte glucocorticoid sensitivity (GCS) pertains to the responsivity of leukocytes to the regulating actions of glucocorticoids, such as cortisol. Impaired endocrine regulation may link the metabolic syndrome (MetS) to the development of cardiovascular disease. We tested if the physiological association between endogenous cortisol levels and peripheral leukocyte composition becomes disrupted in individuals with MetS.MethodsMetS was assessed among 689 German industrial employees. The covariance between cortisol levels and hematologic parameters (i.e., proportions of neutrophils and lymphocytes) and their ratio was explored, which has been proposed as a proxy for GCS in vivo. Cortisol level before blood collection was assessed by repeated saliva collection, and the area under the curve was calculated. Linear regression models were adjusted for potential confounders including age, gender, BMI, income, and lifestyle factors.ResultsCortisol levels did not differ between subgroups. Participants without MetS (n = 552) showed the expected association of cortisol with hematologic parameters (β = 0.207 to 0.216; p values < 0.001). No association (β = 0.078 to 0.083; p values > 0.10) was found among those with MetS (n = 137), consistent with a reduced GCS. Analyses of separate MetS components showed that reduced GCS was associated specifically with decreased high-density lipoprotein and elevated fasting plasma glucose.ConclusionsUtilizing a novel statistical approach to infer GCS, this study provided first epidemiological evidence of aberrant physiological regulation of leukocyte distribution by endogenous cortisol levels among individuals with MetS. These findings underline the idea that MetS may involve disruption of endocrine-immune regulation.