Showing papers by "University of Delaware published in 1993"

Toward a Theory of Organizational Creativity

Abstract: In this article we develop a theoretical framework for understanding creativity in complex social settings. We define organizational creativity as the creation of a valuable, useful new product, service, idea, procedure, or process by individuals working together in a complex social system. The starting point for our theoretical development is provided by the interactionist model of creative behavior developed by Woodman and Schoenfeldt (1989). This model and supporting literature on creative behavior and organizational innovation are used to develop an interactional framework for organizational creativity. The theoretical framework is summarized by three propositions that can effectively guide the development of testable hypotheses.

The Common Ingroup Identity Model: Recategorization and the Reduction of Intergroup Bias

Abstract: This chapter introduces the common ingroup identity model as a means of reducing intergroup bias. This model proposes that bias can be reduced by factors that transform members' perceptions of group boundaries from “us” and “them” to a more inclusive “we”. From this perspective, several features specified by the contact hypothesis (e.g. co-operative interaction) facilitate more harmonious intergroup interactions, at least in part, because they contribute to the development of a common ingroup identity. In this chapter, we describe laboratory and field studies that are supportive of the model; we also relate the model to earlier work on aversive racism.

Fundamentals of Poroelasticity

Abstract: Publisher Summary This chapter focuses on fundamentals of poroelasticity. The presence of a freely moving fluid in a porous rock modifies its mechanical response. Two mechanisms play a key role in the interaction between the interstitial fluid and the porous rock: (i) an increase of pore pressure induces a dilation of the rock; and (ii) compression of the rock causes a rise of pore pressure, if the fluid is prevented from escaping the pore network. These coupled mechanisms bestow an apparent time-dependent character to the mechanical properties of the rock. If excess pore pressure, induced by compression of the rock, is allowed to dissipate through diffusive fluid mass transport, further deformation of the rock progressively takes place. The rock is more compliant under drained conditions than undrained ones. The chapter discusses the formulation and analysis of coupled deformation–diffusion processes, within the framework of the Biot theory of poroelasticity. The Biot model of a fluid-filled porous material is constructed on the conceptual model of a coherent solid skeleton and a freely moving pore fluid.

Four Systems for Emotion Activation: Cognitive and Noncognitive Processes

Abstract: The significant role of emotions in evolution and adaptation suggests that there must be more than 1 mechanism for generating them. Nevertheless, much of current emotion theory focuses on cognitive processes (appraisal, attribution, and construal) as the sole, or primary, means of eliciting emotions. As an alternative to this position, the present model describes 4 types of emotion-activating systems, 3 of which involve noncognitive information processing. From an evolutionary-developmental perspective, the systems maybe viewed as a loosely organized hierarchical arrangement, with neural systems, the simplest and most rapid, at the base and cognitive systems, the most complex and versatile, at the top. The emotion-activating systems operate under a number of constraints, including genetically influenced individual differences. The hierarchical organization of the systems for generating emotions provides an adaptive advantage.

Comprehensive effects of alcohol: Development and psychometric assessment of a new expectancy questionnaire.

Abstract: A comprehensive measure of alcohol outcome expectancies was developed through the use of exploratory and confirmatory factor analyses. The questionnaire assesses both positive and negative expected effects of alcohol as well as the subjective evaluation of those effects. The measure was found to demonstrate adequate internal consistency, temporal stability, and construct validity. Criterion validity was demonstrated through structural regression analyses of the independent and combined influences of outcome expectancies and subjective evaluation on three measures of alcohol use. Information on subjects' dose-related expectancies provided further validation of the expectancy construct and yielded information about the effects people associate with drinking different amounts of alcohol

Attachment and emotion regulation during mother-teen problem solving: a control theory analysis.

Abstract: We present a control theory analysis of adolescents' attachment strategies in the Adult Attachment Interview (AAI). In Study 1, Q-sort prototypes for secure/anxious and deactivating/hyperactivating strategies were used to differentiate between Main and Goldwyn's AAI classifications. In Study 2, we examined how AAI strategies were associated with emotion regulation during mother-teen problem solving. 4 aspects of mother-teen problem solving (dysfunctional anger, support/validation, avoidance of problem solving, and maternal dominance) were used to predict teens' AAI strategies. Teens with secure strategies engaged in problem-solving discussions characterized by less dysfunctional anger and less avoidance of problem solving. In addition, attachment security showed a curvilinear relation with maternal dominance, indicating that secure teens maintained balanced assertiveness with their mothers. Teens with deactivating strategies engaged in problem-solving interactions characterized by higher levels of maternal dominance and dysfunctional anger. The contribution of attachment strategies to teens' autonomy and to transformations in mother-teen relationships is discussed.

Analysis of acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) for the estimation of potential toxicity in aquatic sediments

Abstract: Acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) are operationally defined methods for the analysis of sulfide and associated metals in aquatic sediments. The SEM-to-AVS ratio has been useful in explaining the results of bioassay tests of metal toxicants. This paper describes apparatus that can be used in the evolution of sulfide from sediments and a method for the analysis of the evolved sulfide and the liberated metal. The method was studied with respect to gas flow rate, digestion time, and acid concentration. Liberated and trapped sulfide was determined by a colorimetric method of analysis. Using the apparatus and conditions described in this paper, the colorimetric method of analysis. Using the apparatus and conditions described in this paper, the colorimetric method of analysis is capable of detecting AVS at concentrations normally encountered with a recovery of sulfide of at least 90%. High precision is possible if this apparatus is used. The limit of detection of the method is approximately 0.01 [mu]mol/g dry sediment added 6 m HCl to produce a final concentration of approximately 1 M for the release of the AVS and SEM from unheated samples. The authors found that sulfide was not released from pyrite (FeS[sub 2]) ormore » copper sulfide (CuS) under the conditions. the liberation of copper from the two studied sediments indicates that copper was probably associated with another phase in these sediments. AVS is stable for several weeks in refrigerated or frozen samples.« less

Stability of emotion experiences and their relations to traits of personality.

Abstract: The article presents a theoretical framework for studying emotion-personality relations and an empirical study of the stability of 88 normal middle-class mothers' emotion experiences and their relations to personality during the 3 years after childbirth. Ss completed the Differential Emotions Scale (DES), Eysenck's Personality Questionnaire, Jackson's Personality Research Form, and Zuckerman's Sensation Seeking Scale. The DES demonstrated stability over 3 years. There was individual stability despite changes in group means during the postpartum period. Positive emotionality, as well as the discrete emotions of interest, enjoyment, and shyness, predicted Extraversion. Negative emotionality and the discrete negative emotions were significant predictors of Neuroticism. Positive emotionality was inversely related to Neuroticism. There were expectable correlations among specific emotions and primary traits of personality.

Scheduling algorithms for multihop radio networks

Abstract: Algorithms for transmission scheduling in multihop broadcast radio networks are presented. Both link scheduling and broadcast scheduling are considered. In each instance, scheduling algorithms are given that improve upon existing algorithms both theoretically and experimentally. It is shown that tree networks can be scheduled optimally and that arbitrary networks can be scheduled so that the schedule is bounded by a length that is proportional to a function of the network thickness times the optimum. Previous algorithms could guarantee only that the schedules were bounded by a length no worse than the maximum node degree times optimum. Since the thickness is typically several orders of magnitude less than the maximum node degree, the algorithms presented represent a considerable theoretical improvement. Experimentally, a realistic model of a radio network is given and the performance of the new algorithms is studied. These results show that, for both types of scheduling, the new algorithms (experimentally) perform consistently better than earlier methods. >

Response of the photosynthetic apparatus of Phaeodactylum tricornutum (Bacillariophyceae) to nitrate, phosphate, or iron starvation

Abstract: The effects of nitrate, phosphate, and iron starvation and resupply on photosynthetic pigments, selected photosynthetic proteins, and photosystem II (PSII) photochemistry were examined in the diatom Phaeodactylum tricornutum Bohlin (CCMP 1327). Although cell chlorophyll a (chl a) content decreased in nutrient-starved cells, the ratios of light-harvesting accessory pigments (chl c and fucoxanthin) to chl a were unaffected by nutrient starvation. The chl a-specific light absorpition coefficient (a*) and the functional absorption cross-section of PSII (σ) increased during nutrient starvation, consistent with reduction of intracellular self-shading (i.e. a reduction of the “package effect”) as cells became chlorotic. The light-harvesting complex proteins remained a constant proportion of total cell protein during nutrient starvation, indicating that chlorosis mirrored a general reduction in cell protein content. The ratio of the xanthophylls cycle pigments diatoxanthin and diadinoxanthin to chl a increased during nutrient starvation. These pigments are thought to play a photo-protective role by increasing dissipation of excitation energy in the pigment bed upstream from the reaction centers. Despite the increase in diatoxanthin and diadinoxanthin, the efficiency of PSII photochemistry, as measured by the ration of variable to maximum fluorescence (Fv/Fm) of dark-adapted cells, declined markedly under nitrate and iron starvation and moderately under phosphate starvation. Parallel to changes in Fv/Fm were decreases in abundance of the reaction center protein D1 consistent with damage of PSII reaction centers in nutrient-starved cells. The relative abundance of the carboxylating enzyme, ribulose bisphosphate carboxylase/oxygenase (RUBISCO), decreased in response to nitrate and iron starvation but not phosphate starvation. Most marked was the decline in the abundance of the small subunit of RUBISCO in nitrate-starved cells. The changes in pigment content and fluorescence characteristics were typically reversed within 24 h of resupply of the limiting nutrient.

Reevaluating the costs of teenage childbearing.

Abstract: Teenage childbearing in the United States has long been regarded as an important social problem with substantial costs to teen mothers and their children. Recently, however, several researchers have argued that the apparent negative effects of teenage childbearing primarily reflect unmeasured family background rather than the true consequences of a teen birth. To distinguish the effect of teen childbearing from that of family background, we use data from the Panel Study of Income Dynamics and compare teen mothers with their sisters. We find that accounting for unobserved family background reduces, but does not eliminate, the estimated consequences of early childbearing. Statistically significant and quantitatively important effects of teen parenthood remain for high school graduation, family size, and economic well-being.

Phase Behavior of Aqueous Mixtures of Cetyltrimethylammonium Bromide (CTAB) and Sodium Octyl Sulfate (SOS)

Abstract: The phase behavior and aggregate morphology of mixtures of the oppositely charged surfactants cetyltrimethylammonium bromide (CTAB) and sodium octyl sulfate (SOS) are explored with cryotransmission electron microscopy, quasielastic light scattering, and surface tensiometry. Differences in the lengths of the two hydrophobic chains stabilize vesicles relative to other microstructures (e.g., liquid crystalline and precipitate phases), and vesicles form spontaneously over a wide range of compositions in both CTAB-rich and SOS-rich solutions. Bilayer properties of the vesicles depend on the ratio of CTAB to SOS, with CTAB-rich bilayers stiffer than SOS-rich ones. We observe two modes of microstructural transition between micelles and vesicles. The first transition, between rodlike micelles and vesicles, is first order, and so there is macroscopic phase separation. This transition occurs in CTAB-rich solutions and in SOS-rich solutions at higher surfactant concentrations. In the second transition mode, mixtures...

Predictive neutrino spectrum in minimal SO(10) grand unification

Abstract: We show that in minimal SO(10) models where the fermions have Yukawa couplings to only one (complex) 10 and one 126 of Higgs scalars the standard model doublet contained in the 126 receives an induced vacuum expectation value at tree level. In addition to correcting the bad asymptotic mass relations ${\mathit{m}}_{\mathit{d}}$=${\mathit{m}}_{\mathit{e}}$ and ${\mathit{m}}_{\mathit{s}}$=${\mathit{m}}_{\mathrm{\ensuremath{\mu}}}$, this also leads to a predictive neutrino spectrum. We find that (i) the ${\ensuremath{ u}}_{\mathit{e}\mathrm{\ensuremath{-}}}$${\ensuremath{ u}}_{\mathrm{\ensuremath{\mu}}}$ mixing angle lies in the range sin${\mathrm{\ensuremath{\theta}}}_{\mathit{e}\mathrm{\ensuremath{\mu}}}$=0\char21{}0.3, (ii) sin${\mathrm{\ensuremath{\theta}}}_{\mathit{e}\mathrm{\ensuremath{\tau}}}$\ensuremath{\simeq}3\ensuremath{\Vert}${\mathit{V}}_{\mathit{t}\mathit{d}}$\ensuremath{\Vert}\ensuremath{\simeq}0.05, (iii) sin${\mathrm{\ensuremath{\theta}}}_{\mathrm{\ensuremath{\mu}}\mathrm{\ensuremath{\tau}}}$\ensuremath{\simeq}3\ensuremath{\Vert}${\mathit{V}}_{\mathit{c}\mathit{b}}$\ensuremath{\Vert}=0.12\char21{}0.16, and (iv) ${\mathit{m}}_{\ensuremath{ u}\mathrm{\ensuremath{\tau}}}$/${\mathit{m}}_{\ensuremath{ u}\mathrm{\ensuremath{\mu}}}$\ensuremath{\ge}${10}^{3}$, implying that ${\ensuremath{ u}}_{\mathrm{\ensuremath{\mu}}\mathrm{\ensuremath{-}}}$${\ensuremath{ u}}_{\mathrm{\ensuremath{\tau}}}$ oscillations should be accessible to forthcoming experiments.

Nearly incompressible fluids. II - Magnetohydrodynamics, turbulence, and waves

Abstract: The theory of nearly incompressible (NI) fluid dynamics developed previously for hydrodynamics is extended to magnetohydrodynamics (MHD). On the basis of a singular expansion technique, modified systems of fluid equations are derived for which the effects of compressibility are admitted only weakly in terms of the different possible incompressible solutions (thus ‘‘nearly incompressible MHD’’). NI MHD represents the interface between the compressible and incompressible magnetofluid descriptions in the subsonic regime. The theory developed here does not hold in the presence of very large thermal, gravitational, or field gradients. It is found that there exist three distinct NI descriptions corresponding to each of the three possible plasma beta (β ≡ the ratio of thermal to magnetic pressure) regimes (β≪1, β∼1, β≫1). In the β≫1 regime, the compressible MHD description converges in the low Mach number limit to the equations of classical incompressible three‐dimensional (3‐D) MHD. However, for the remaining plasma beta regimes, the imposition of a large dc magnetic field forces the equations of fully compressible 3‐D MHD to converge to the equations of 2‐D incompressible MHD in the low Mach number limit. The ‘‘collapse in dimensionality’’ corresponding to the different plasma beta regimes clarifies the distinction between the 3‐D and 2‐D incompressible MHD descriptions (and also that of 21/2‐D incompressible MHD). The collapse in dimensionality that occurs as a result of a decreased plasma beta can carry over to the weakly compressible corrections. For a β∼1 plasma, Alfven waves propagate parallel to the applied magnetic field (reminiscent of reduced MHD), while for a β≪1 magnetofluid, quasi‐1‐D long‐wavelength acoustic modes propagate parallel to the applied magnetic field. The detailed theory of weakly compressible corrections to the various incompressible MHD descriptions is presented and the implications for the solar wind emphasized.

Attachment Stimulates Exopolysaccharide Synthesis by a Bacterium

Abstract: This study examined the hypothesis that solid surfaces may stimulate attached bacteria to produce exopolymers. Addition of sand to shake-flask cultures seemed to induce exopolymer synthesis by a number of subsurface isolates, as revealed by optical microscopy. Several additional lines of evidence indicated that exopolymer production by attached cells (in continuous-flow sand-packed columns) was greater than by their free-living counterparts. Total carbohydrates and extracellular polysaccharides, both normalized to cell protein, were greater (2.5- and 5-fold, respectively) for attached cells than for free-living cells. Also, adsorption of a polyanion-binding dye to the exopolymer fraction was sixfold greater for attached cells than for unattached cells. When surface-grown cells were resuspended in fresh medium, exopolymer production decreased to the level characteristic of unattached cells, which ruled out the possibility that attached cells comprised a subpopulation of sticky mucoid variants. The mechanism by which attachment stimulated exopolymer synthesis did not involve changes of the specific growth rate, growth stage, or limiting nutrient.

Religious and nonreligious coping with the death of a friend

Abstract: Interviewed 96 undergraduates about their coping with the recent death of a close friend. Measures assessed characteristics of: (a) the event (e.g., months since death); (b) the respondent (e.g., intrinsic and extrinsic religiousness); (c) religious and nonreligious causal appraisals; (d) religious and nonreligious coping strategies; and (e) general and event-related outcomes (e.g., dysphoria, personal growth). Data were analyzed by path analysis and models were constructed for each outcome variable, showing how each of the elements of the coping process was predictive of later elements in the models. As expected, person and event variables, attributions, and coping activities were predictive of each outcome in complex ways. One intriguing set of findings concerned the complex role of intrinsic religiousness, which was indirectly related to increased personal growth and decreased dysphoria, but was directly related to increased event-related distress. Overall, the results point to the important role of religion in the coping process.

A Comparison of Contingent Preference Models

Abstract: I compare the informational efficiencies of contingent rating, contingent ranking, and two contingent paired‐comparison methods as alternatives to the referendum contingent valuation method. The contingent rating method is hypothesized to be most efficient because ratings convey information on preference intensities and can uniquely represent respondent indifference or ambivalence. Survey data on hunters' ratings of alternative hypothetical hunting trips are used to estimate four alternative indirect utility models from which marginal willingness‐to‐pay measures for individual trip attributes are derived. Model comparison, WTP estimates, and their confidence intervals confirm the relative efficiency of the contingent rating approach.

Normative Images of Communication Media Mass and Interpersonal Channels in the New Media Environment

Abstract: This study is an extension of earlier uses and gratifications research that identified normative images of mass media. The article considers how well 12 different mass and interpersonal communication channels fill 11 communication needs. A sample of 649 adults completed self-administered questionnaires, the responses of which were submitted to cluster analysis, which identified five channel clusters: Video, Interpersonal, Print, Computer, and Audio. In general, the Interpersonal cluster (conversation and telephone) was rated the most useful at filling various needs, with Computer rated the least useful. Consistent with previous research, clusters that were most useful at filling personal needs were rated highest in social presence. The discussion relates this study's findings to previous research and notes implications for research on the newer communication technologies.

The Role of Project Completion Information in Resource Allocation Decisions

Abstract: Prior studies have suggested that "sunk costs," the amount of money already invested in a project, influence resource allocation decisions but have often confounded sunk costs with the degree to which a project is completed. To address this issue, we varied information about both sunk costs and project completion in two experiments. Our results suggest that degree of project completion may dominate any sunk cost effects that are present in resource allocation decisions. An expanding literature from a variety of theoretical paradigms suggests that, contrary to normative models of decision making, consideration of sunk costs-the amount of a budget invested in a project-may enter into resource allocation decisions. In the reported study, we focused on situations in which a decision maker faces a choice between continued investment in a project or withdrawal with certain loss of some or all prior investments. According to traditional economic theory, a rational decision maker in the situation just described would consider only incremental costs and benefits. However, a growing body of research suggests that sunk costs may influence the decision to continue investment in an ongoing project. For example, Arkes and Blumer (1985) found that subjects faced with a decision to invest more funds in an ongoing research and development project were more willing to make the investment than those asked if they would invest the same amount of funds to start up the same R&D project. In a replication study using five levels of prior investment, Garland (1990) found a linear relationship between the amount of sunk costs and willingness to continue investment in the project. Faced with mounting evidence for the existence of irrational sunk cost effects on resource allocation decisions, we examined the studies in which such effects have been observed. Such an examination revealed that at least two variables are in need of closer scrutiny. First, a number of studies have used decision scenarios in which sunk costs have been confounded with the degree of project completion. Second, most studies have included negative information about project success as a constant condition.

Stocks and dynamics of bacterioplankton carbon during the spring bloom in the eastern North Atlantic Ocean

Abstract: Bacterial biomass increased five-fold in the euphotic zone (from 450 to 2250 mgC m−2) in response to the spring phytoplankton bloom in the eastern North Atlantic Ocean (Lat. 47°N, Long. 20°W) in 1989. Bacterial biomass accounted for about 20–30% of the particulate organic carbon (POC) above 50 m and a somewhat larger fraction in the layer below. Bacterial production averaged about 30% of primary production and remained rather constant while the primary production varied from 600 to 1500 mgC m−2 day−1 in response to event-scale changes in irradiance. Thus bacterial production varied from 15 to 80% of the concurrent primary production, with peaks occurring on overcast days when photosynthesis was low. Bacterial production in both the euphotic zone and the layer immediately below appeared to respond to the meteorologically-driven variations in photosynthesis with a time lag of 3–4 days, consistent with estimates of turnover rates of 0.2 day−1. In the upper layer incorporation of dissolved free amino acids supported about 20% of the production. The bacterial carbon demand at peak production required subsidies of carbon from the bulk POC and/or DOC pools. In the lower layer, decomposition of the vertical flux of sinking POC may have supported about half the mean production. Our bacterial production estimates for the 50–150 m layer are consistent with vertical flux estimates from drifting sediment traps and support other observations in suggesting that very large amounts of primary production pass through the DOC pool on short time-scales. Our observations suggest a spring-time North Atlantic condition for the microbial foodweb in which bacterial biomass makes up a relatively small part of the plankton carbon stock, but cycles rapidly (0.1–0.3 day−1) and commands a large share of the carbon cycling in the upper ocean. Through extensive metabolism of DOC and sinking POC in the upper 200 m, the bacterioplankton act as a selective gate through which some fraction of the products of primary production are exported into the oceanic interior.

Melting and freezing behavior of indium metal in porous glasses

Abstract: The size-dependent melting and freezing behavior of In metal in porous silica glasses with mean pore diameters between 6 and 141 nm has been studied by differential scanning calorimetry. The melting and freezing temperatures of the pore In were always less than the corresponding bulk values, and varied in inverse proportion to the diameter of the confining silica pores. In the smallest pores the latent heat of fusion was also determined, and found to be about one-third of its bulk value. The observed size dependence of the melting temperature was in good agreement with the predictions of thermodynamic treatments of melting in finite systems, and allowed the solid-liquid interfacial free energy to be estimated for several different geometrical models. The measured latent heat, however, was smaller than expected based on thermodynamic considerations. No evidence for an energy barrier separating the solid from the liquid was found.

LUM filters: a class of rank-order-based filters for smoothing and sharpening

Abstract: A new class of rank-order-based filters, called lower-upper-middle (LUM) filters, is introduced. The output of these filters is determined by comparing a lower- and an upper-order statistic to the middle sample in the filter window. These filters can be designed for smoothing and sharpening, or outlier rejection. The level of smoothing done by the filter can range from no smoothing to that of the median filter. This flexibility allows the LUM filter to be designed to best balance the tradeoffs between noise smoothing and signal detail preservation. LUM filters for enhancing edge gradients can be designed to be insensitive to low levels of additive noise and to remove impulsive noise. Furthermore, LUM filters do not cause overshoot or undershoot. Some statistical and deterministic properties of the LUM filters are developed, and a number of experimental results are presented to illustrate the performance. These experiments include applications to 1D signals and to images. >

Biomass and production of heterotrophic bacterioplankton in the oceanic subarctic Pacific

Abstract: As part of the Subarctic Pacific Ecosystem Research (SUPER) program, we measured the abundance and biomass production of heterotrophic bacterioplankton in the subarctic Pacific and compared these parameters with those of phytoplankton during four cruises in 1987 and 1988. Bacterial biomass was about equal to phytoplankton biomass during all cruises. Based on rates of bacterial biomass production and assuming a growth efficiency of 50%, we estimate that heterotrophic bacteria consumed 10% (June 1987) to 24% (August 1988) of primary production in the euphotic zone. These percentages are low compared with other aquatic ecosystems, apparently due to low bacterial growth rates ( −1 ) iin the subarctic Pacific. In contrast, phytoplankton growth rates were much higher (0.1–8.8 day −1 ). Bacterial growth rates were limited by the supply of dissolved organic matter and temperature. Even with these low growth rates, however, bacterial biomass and rates of biomass production increased by 2–5-fold in May and August 1988, changes that were not obviously related to corresponding changes in phytoplankton biomass nor primary production. Heterotrophic bacterioplankton constitutes a large reservoir of carbon and nitrogen that needs to be considered in modelling ecosystem dynamics of the subarctic Pacific.

Natural suppression of Higgsino-mediated proton decay in supersymmetric SO(10).

Abstract: In supersymmetric grand unified theories, proton decay mediated by the color-triplet Higgsino is generally problematic and requires some fine-tuning of parameters. We present a mechanism which naturally suppresses such dimension-5 operators in the context of SUSY SO(10). The mechanism, which implements natural doublet-triplet splitting using the adjoint Higgs boson, converts these dimension-5 operators effectively into dimension 6. By explicitly computing the Higgs spectrum and the resulting threshold uncertainties we show that the successful prediction of ${{sin}^{2}\ensuremath{\theta}}_{W}$ is maintained as a prediction in this scheme. It is argued that only a weak suppression of the Higgsino-mediated proton decay is achievable within SUSY SU(5) without fine-tuning, in contrast to a strong suppression in SUSY SO(10).