首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
The neurosciences have advanced to the point that we can now treat consciousness as a scientific problem like any other. The problem is to explain how brain processes cause consciousness and how consciousness is realized in the brain. Progress is impeded by a number of philosophical mistakes, and the aim of this paper is to remove nine of those mistakes: (i) consciousness cannot be defined; (ii) consciousness is subjective but science is objective; (iii) brain processes cannot explain consciousness; (iv) the problem of 'qualia' should be set aside; (v) consciousness is epiphenomenal; (vi) consciousness has no evolutionary function; (vii) a causal account of consciousness is necessarily dualistic; (viii) science is reductionistic, so a scientific account of consciousness would show it reducible to something else; and (ix) an account of consciousness must be an information processing account.  相似文献   

2.
Inrecentyears ,Komiyaetal.[1] havefoundthatrareearthsionsmaybeoneofthestrongestcutre agentsofnucleicacids .Theexperimentalresults ,thatrareearthsrepresscancersonwholeanimalbodiesandonhumanbodies(invitro) ,indicatedthatrareearthselementsactuallyhavestrongf…  相似文献   

3.
The following conclusions appear to be justified: (1) There is no evidence that happiness in marriage is a function of understanding the mate or is related to the similarity of selves of the mates. (2) Evidence indicates that marital happiness is associated with similarity of self perceptions of the mates. (3) Husbands and wives are no more similar in self perceptions than randomly paired men and women. (4) Marital happiness is related to the conformity of men to self perceptions of their sex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
Reviews behavioral literature on childhood fears, including conceptual models, normative research, and fear-reduction studies. The main conclusions are as follows: (a) The information value of nearly 60 yrs of normative studies is meager, and their continuation is of doubtful value. (b) Most research has been limited to laboratory studies of mildly to moderately fearful children, and few data exist on severe fears studied in the child's natural environment or on the clinical prevalence of fear. (c) Cognitive and developmental factors have been largely ignored. (d) Modeling is the most frequently used and reliably effective fear-reduction strategy. (e) A cognitive, verbal-mediation approach is promising but is not yet sufficiently researched. (f) There is little evidence that systematic desensitization or contingency management strategies are effective. Implications for large-scale fear reduction and prevention are discussed. The need for research that recognizes the complex paradigms of children's fears is suggested. (4 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
Research is reviewed on 6 theoretical propositions central to psychodynamic psychotherapy: (1) The establishment of an alliance is important to successful outcome; (2) the patient displays a central relationship theme (transference); (3) transference interpretations are helpful; (4) the therapist aims at accurate interpretations of the transference; (5) the patient gains understanding of self and the relationship pattern; and (6) the patient's improvement is reflected in changes in the relationship pattern, although the pattern is still evident. We suggest concepts that are in need of research development: internalization, resistance, working through, self-understanding and insight, and the therapist's adherence to recommended techniques. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
7.
Myeloperoxidase plays a fundamental role in oxidant production by neutrophils. The enzyme uses hydrogen peroxide to oxidize chloride (Cl-), bromide (Br-), iodide (I-), and the pseudohalide thiocyanate (SCN-) to their respective hypohalous acids. This study for the first time presents transient kinetic measurements of the oxidation of these halides and thiocyanate by the myeloperoxidase intermediate compound I, using the sequential mixing stopped-flow technique. At pH 7 and 15 degrees C, the two-electron reduction of compound I to the native enzyme by Cl- has a second-order rate constant of (2.5 +/- 0.3) x 10(4) M(-1) s(-1), whereas reduction of compound I by SCN- has a second-order rate constant of (9.6 +/- 0.5) x 10(6) M(-1) s(-1). Iodide [(7.2 +/- 0.7) x 10(6) M(-1) s(-1)] is shown to be a better electron donor for compound I than Br- [(1.1 +/- 0.1) x 10(6) M(-1) s(-1)]. The pH dependence studies suggest that compound I reduction by (pseudo-)halides is controlled by a residue with a pKa of about 4.6. The protonation of this group is necessary for optimum (pseudo-)halide anion oxidation. These transient kinetic results are underlined by steady-state spectral and kinetic investigations. SCN- is shown to be most effective in shifting the system myeloperoxidase/hydrogen peroxide from the peroxidatic cycle to the halogenation cycle, whereas iodide is shown to be more effective than bromide which in turn is much more effective than chloride. Decreasing pH increases the rate of this transition. Our results show that thiocyanate is an important substrate of myeloperoxidase in most environments and that hypothiocyanate is likely to contribute to leukocyte antimicrobial activity.  相似文献   

8.
The magnetic properties of Nd_(16)Fe_(77)B_7 and Nd_(16)Fe_((61-x))Co_(16)Ga_xB_7(x=0,1,2,4,7)have been measured.Itis found that the remanent magnetization(Br),maximum energy product(BH)_(max)and the Curie temperature(T_c)decrease with the increase of Ga content.The coercive force(He)increases with the increase of Ga contentwhen x is less than 2,but decreases when x>2.At x=2,the coercive force reaches its maximum value.It is alsofound in all the samples investigated that there is a linear relationship between H_c~(1/2)and T~(2/3),which can not beexplained by Gaunt's wall barrier model.The temperature dependence of the calculated values of H_v and(4bf)has been discussed.  相似文献   

9.
The aim of the present study was to characterize pharmacologically endothelin receptors that are present in human umbilical vessels. 2. Endothelin-1 (ET-1) and endothelin-2 (ET-2) are potent stimulants of both the human umbilical artery (pEC50 7.9 and 7.5) and vein (pEC50 8.1 and 8.0). Endothelin-3 (ET-3) is inactive on the artery but contracts the vein (pEC50 7.6). IRL1620 is inactive in both vessels. The order of potency of agonists is suggestive of a typical ET(A) receptor in the artery (ET-1 = ET-2 > > ET-3) and a mixture of ET(A) and ET(B) receptors in the vein (ET-1 = ET-2 > or = ET-3). 3. The selective ET(A) receptor antagonist, BQ123, competitively inhibits the effect of ET-1 in the human umbilical artery (pA2 6.9), while in the vein, only a mixture of BQ123 and BQ788 (a selective ET(B) antagonist) weakly displaces to the right of the cumulative concentration-response curve to ET-1. Contractions induced by ET-3 in the vein are inhibited by BQ788 (pA2 7.6), but not by BQ123. 4. Inhibition of Ca2+ channels by nifedipine (0.1 microM) is accompanied by a significant decrease of the maximal response to ET-1 by 40% in the artery and by 30% in the vein. The response of the vein to ET-3 is almost abolished by nifedipine. 5. The results indicate that: (i) endothelins contract the human isolated umbilical artery via stimulation of an ET(A) receptor type; (ii) the contraction induced by ET-1 in the vein is mediated by both ET(A) and ET(B) receptors, while ET-3 stimulates the ET(B) receptor; (iii) the contribution of Ca2+ channels to the contraction mediated by the ET(B) receptor appears to be more important than to that mediated by the ET(A) receptor.  相似文献   

10.
铸造铝硅合金中硅相变质机制的电子理论研究   总被引:3,自引:0,他引:3  
张辉  张国英  魏国柱 《稀有金属》2003,27(5):605-608
通过计算机编程构造出了Al-Si铸造合金中Si(金刚石结构)相(111)表面及稀土导致的(111)孪晶表面的原子结构模型,利用连分敷方法计算了稀土处于表面及孪晶表面这两种位置时的电子结构。稀土原子处于孪晶表面时的结构能明显比处于Si(111)表面大,说明稀土原子容易占据孪晶表面的位置;稀土原子处于孪晶界时的环境敏感镶嵌能比处于表面小,说明稀土处于孪晶表面时比较稳定,同时原子间的键级积分计算也表明稀土能够占据孪晶表面的位置且在此处较稳定。这就从电子层次解释了稀土导致孪晶的事实,阐明了稀土在Al-Si铸造合金中的变质机制。  相似文献   

11.
Lipoprotein(a) [Lp(a)] is an atherogenic lipoprotein which is similar in structure to, but metabolically distinct from, LDL. Factors regulating plasma concentrations of Lp(a) are poorly understood. Apo(a), the protein that distinguishes Lp(a) from LDL, is highly polymorphic, and apo(a) size is inversely correlated with plasma Lp(a) level. Even within the same apo(a) isoform class, however, plasma Lp(a) concentrations vary widely. A series of in vivo kinetic studies were performed using purified radiolabeled Lp(a) in individuals with the same apo(a) isoform but different Lp(a) levels. In a group of seven subjects with a single S4-apo(a) isoform and Lp(a) levels ranging from 1 to 13.2 mg/dl, the fractional catabolic rate (FCR) of 131I-labeled S2-Lp(a) (mean 0.328 day-1) was not correlated with the plasma Lp(a) level (r = -0.346, P = 0.45). In two S4-apo(a) subjects with a 10-fold difference in Lp(a) level, the FCR's of 125I-labeled S4-Lp(a) were very similar in both subjects and not substantially different from the FCRs of 131I-S2-Lp(a) in the same subjects. In four subjects with a single S2-apo(a) isoform and Lp(a) levels ranging from 9.4 to 91 mg/dl, Lp(a) concentration was highly correlated with Lp(a) production rate (r = 0.993, P = 0.007), but poorly correlated with Lp(a) FCR (mean 0.304 day-1). Analysis of Lp(a) kinetic parameters in all 11 subjects revealed no significant correlation of Lp(a) level with Lp(a) FCR (r = -0.53, P = 0.09) and a strong correlation with Lp(a) production rate (r = 0.99, P < 0.0001). We conclude that the substantial variation in Lp(a) levels among individuals with the same apo(a) phenotype is caused primarily by differences in Lp(a) production rate.  相似文献   

12.
Discusses D. S. Holmes's (see record 1982-03660-001) critique of the author's (see record 1982-03692-001) article on self-serving biases in person perception. Holmes's critique is not compelling for 2 reasons: (a) His contention that there is no evidence to support classical projection is defensible only if an essentially untestable concept, the unconscious, is considered to be a vital component of the mechanism; and (b) his conclusions regarding the stress-reduction effects of attributive projection rely on research that is methodologically flawed or unavailable for public scrutiny. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
除铬是含铬电镀污泥湿法冶金过程重要步骤.针对磷酸盐沉淀法从溶液中净化除铬过程进行热力学分析,绘制了25 ℃时Me-P-H2O(Me: Cr(III), Zn(II), Cu(II), Fe(II), Fe(III), Ni(II))系组浓度对数-pH图,利用热力学平衡图对磷酸盐沉淀法从含铁等金属元素中净化除铁和磷酸铬碱分解过程进行热力学分析.结果表明,pH值为1.0 ~ 5.0磷酸盐形成由易至难依次为Cr(III)>Fe(III) >Fe(II)>Ni(II)>Cu(II)>Zn(II); 磷酸盐沉淀法难以有效地将Cr(III)与Fe(III)分离,而可分离Cr(III)和Fe(II),且较优pH约为2;整个pH值范围Me-P-H2O系可以分为难溶磷酸盐稳定区、Me(OH)n稳定区; 高pH区磷酸盐中的Me转变为稳定的Me(OH)n,实现磷酸盐碱分解.验证实验表明,加入1.1倍理论量的磷酸钠,控制沉淀pH值为2.0,铬、铁、锌、铜、镍沉淀率分别为94.12 %、5.51 %、0.33 %、0.22 %、0.34 %; 氢氧化钠分解磷酸铬时,磷、铬浸出率分别为90.63 %、5.10 %,实现磷铬有效分离.实验与理论基本相符.   相似文献   

14.
Describes initial experiences in the development of a field of applied animal psychology dealing with the behavioral problems of pet animals. A team approach is suggested where (a) the pet's problem is analyzed; (b) a remedial training program based on classical and operant conditioning is used; (c) the owner is instructed in the implementation of the program; and (d) a follow-up assessment of the procedure's effectiveness is proposed. The case histories of 3 dogs with behavioral problems are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
Presents a theoretical model for understanding social unrest which is based on the experience of control. It is proposed that social unrest indicates powerlessness and consequently an inability to make self-directed choices to alter one's environment. The model postulates 4 interacting components or sources of behavioral determinants: (a) control from internal organismic states (e.g., impulses), (b) control over these internal states, (c) control over the environment, and (d) control from the environment. It is argued that social unrest must be dealt with in terms of the resources of the social sciences and not in political or managerial priorities. The question of whether social unrest is the outgrowth of the effects of social systems on individuals (overemphasis of control from the environment) or enlightenment regarding the individual's self-directing potential (increased control over the environment) is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
On the basis of a critical review of studies that examined the use of temporal information in the regulation of movement, J. P. Wann (1996) concluded that there is little evidence in favor of the use of tau. Although more experimental work is certainly needed, progress can only be made if (a) the conceptual confusion emanating from a lack of distinction between specification (i.e., information) and what is specified (i.e., relevant property of the environment–actor system) is resolved, and (b) the way in which information is used in the regulation of movement is reconsidered. It is argued that continuous control models incorporating first-order time-to-contact related information not only explain the results obtained but also allow testable accounts of the principles involved in kinematic trajectory formation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
W. C. Follette and A. C. Houts (1996) argued on philosophy-of-science grounds that the Diagnostic and Statistical Manual of Mental Disorders (DSM) is scientifically unprogressive and should be replaced by competing theory-laden manuals. The author responds to their various arguments as follows: (a) The ways things can go wrong with the mind are inherently diverse, so failure to reduce the DSM's categories to 1 parsimonious theory is not necessarily scientifically unprogressive; (b) it is empirically untrue that growth in the number of a taxonomy's categories is inconsistent with scientific progress; (c) progress in theoretically fragmented fields requires shared theory-neutral categories, not theory-laden definitions of basic concepts; (d) at present in the mental health field, theoretical integration is scientifically more progressive than competition, and integration is promoted by the DSM's theory-neutral nosology; and (e) FoIlette and Houts's proposed behaviorist alternative to the DSM is incoherent. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
氨基膦酸树脂吸附铈的研究   总被引:5,自引:1,他引:4  
研究了铈(Ⅲ)在氨基磷酸树脂上的吸附行为。试验结果在pH5.0时,静态饱和吸附容量为197mg/g干树脂;用2mol.L-1HCl洗脱,洗脱率为98.1%;表观速率常数k298=2.71×10-5s-1;等温吸附服从Freundlich经验式;吸附反应中的△Ho=50.0kJ.mol-1,△So=286J.mol-1.K-1,△Go=-35.1kJ.mol-1。树脂功能基与Ce3+的配比为2∶1;并用红外光谱探讨了树脂与铈的成键。  相似文献   

19.
In their comment on the tolerance-noise covariation (TNC) method for decomposing variability by H. Müller and D. Sternad (2003, 2004b), J. B. J. Smeets and S. Louw (see record 2007-01135-017) show that covariation (C), as defined within the TNC method, is not invariant with respect to coordinate transformations and contend that it is, therefore, meaningless. Although the observation is correct, their interpretation is misleading in the following ways: (a) They equate covariation C with the known statistical quantity covariance and noise (N) with standard deviations. The two quantities C and N are conceptually different statistical measures. (b) Dependency on the reference frame is not only a feature of C but of all 3 components. However, such dependency is ubiquitous in motor control. (c) As the frame of reference in biological systems is poorly understood, the TNC method may afford evaluation of different coordinates for control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号