Accessory Unit Research Articles

Not (Officially) in My Backyard

Problem, research strategy, and findings One promising policy approach to addressing housing needs is liberalizing accessory dwelling unit (ADU) development. Yet, understanding the impact of such policy efforts is fundamentally constrained by the inability to quantify and characterize unpermitted ADUs, which may expose homeowners and tenants to legal, financial, and safety risks and confound policy evaluations. We addressed this gap by leveraging computer vision and human annotations to estimate the population of detached ADU constructions in San José (CA). Our contributions are threefold: 1) We estimated the proportion of unpermitted ADU constructions from 2016 to 2020; 2) we describe the demographic, housing market, and parcel characteristics associated with these informal ADUs; and 3) we provide a data set of labeled small buildings, excluding unpermitted detections, for further research. We found that informal ADU construction was substantial—approximately three to four informal units for every formal unit—and more likely in more diverse, dense, and overcrowded neighborhoods. Though our study was limited to analyzing detached ADUs during one time period, we set the stage for further investigations of informal housing across different typologies and over time. Takeaway for practice Our approach demonstrates the promise of computer vision and human annotations to enable more robust, comprehensive, and reliable understanding of actual—not just permitted—housing units. We urge planners and other policymakers to consider the growth patterns of unpermitted ADUs to more optimally and equitably address housing needs.

A high-power-density design method for polymer gear systems via an adaptive non-dominated sorting genetic algorithm III and surrogate sub-models

There is a growing and prevalent trend in the power transmission field of high-performance polymers replacing metallic materials given the strict light-weight requirement. Polymer gears exhibit a low elasticity modulus, high-temperature sensitivity, and increased geometric design flexibility, presenting technical challenges to the straightforward application of metallic design methods to polymer gear systems. This study is centred on the development of a high-power-density polymer gear transmission system for the accessory unit of a gas turbine engine, utilising an adaptive NSGA-III algorithm and surrogate sub-models. A comprehensive assessment indicator for the operating performance of the transmission system is suggested, encompassing gear strength, bearing temperature, and shaft torsional stiffness. The model made it possible to simultaneously optimise forty-six structural parameters, including gear tooth module, web thickness, and bearing clearance. In contrast to the original steel design scheme, the optimised polymer gear transmission system indicated a 49% reduction in weight and a 1.96-fold increase in power density. This presents a method for substituting steel with polymers for effective power transmission.

Architecture and the Accessory Dwelling Unit Revolution: Perspectives from Builders

Architecture and the Accessory Dwelling Unit Revolution: Perspectives from Builders

How Does Real Estate Investor Ownership Mediate Accessory Dwelling Unit (ADU) Asking Rents? Evidence from Austin, TX

Scholarly and popular discourse often describe accessory dwelling units (ADUs) as one of the last bastions of housing affordability, framing “mom and pop” landlords as historically renting out ADUs as a means to earn a passive income, offset mortgage costs, or age in place. As real estate investors enter the market for ADUs, this raises the question of whether ADUs will continue to represent relatively affordable housing packages. Despite growing interest in ADUs among real estate investors, research to date has not examined how investor ownership impacts ADU affordability. This paper investigates how real estate investor ownership mediates unit-level asking rents for ADUs advertised online on the “open market” in Austin, Texas. This analysis finds that owner-occupied and investor-owned ADUs are not listed for significantly different amounts at vacancy, all else equal. However, these results might not translate to the “closed” market for ADUs, which continues to represent a critical source of below-market rate housing. Further, the gap between investor and owner-occupied rents could widen over time, as owner-occupiers provide deeper discounts to tenants they wish to retain. After conducting interviews with owner-occupiers and real estate investors that own ADUs, this research identifies that the rent-setting strategies of the two groups both diverge and converge, further shedding light on findings from the empirical analysis.

Accessory Dwelling Units and Incremental Urbanism: Becoming 'Urban' or just 'Intensive Suburban'?

As suburban environments are increasingly brought into the purview of urban planning, there is an emerging narrative of the importance of 'incremental urbanism' (Pinnegar et al., 2015). For some (Dovey, 2014) this presents an opportunity for a gentler approach to catalyse change in neighbourhoods with established communities and fragmented ownership patterns. Such change is hoped to overcome the perceived shortcomings of car dependency and housing homogeneity that typifies established suburbs. The Accessory Dwelling Unit (ADU) has entered the policy lexicon as an incremental pathway – or blending – from pre-existing suburban environments, where the 'sub' dissipates to leave just 'urban'. This paper presents an analysis of ADUs in Sydney, Australia, where we identify a series of challenges created by the introduction of policies to encourage ADUs in established suburbs. This includes increasing tenure informality and precarity, poor suitability of neighbourhoods for diverse people and households, and increased dependence on shared amenity. We argue that in the absence of any major effort to improve services and infrastructure, there is little evidence that neighbourhoods experiencing a high take-up of ADUs are transitioning to becoming more 'urban'. The fetishization of density in urban policy and development is leading to more 'intensive suburban' blendscapes that encapsulate the worst elements of both suburban and urban morphologies.

The influence of accessory dwelling unit (ADU) policy on the contributing factors to ADU development: an assessment of the city of Los Angeles.

Since the accessory dwelling unit (ADU) has emerged as a policy alternative to increase housing stock and provide affordable options for areas impacted by housing shortages, many local governments recently adopted ADU policies that promote the construction of ADUs. Taking the City of Los Angeles as the study area, this paper examines how the city's ADU ordinance impacts the relationship of the characteristics of the properties and neighborhoods with ADU development by constructing multilevel logistic regression models. The outputs of the models suggest that the ordinance contributes to diversifying the types and locations of the properties and neighborhoods where ADUs are built. The influence of the property characteristics associated with ADU development before the implementation of the ordinance significantly diminished after the ordinance. The outputs also indicate that the ordinance probably attracted ADU developments in the areas with higher accessibility to bus transit. These findings will help planners take appropriate actions and policies that support ADU developments.

The Impact of Legalizing Accessory Dwelling Unit Rentals on Property Values: Evidence from Ogden, Utah

We study the impact of legalizing the rental of Accessory Dwelling Units (ADUs) on property values. We use a dataset of property sales in Ogden, Utah both before and after a policy change legalizing ADU rentals in 2016. We apply repeat sales and differences-in-difference methods to evaluate the impact of the ordinance on property values. Theoretically, the ordinance could increase property values due to the higher expected returns available from ADU rental income, however, potential congestion, noise, and parking issues could alternatively cause property values to decrease. In our analysis, we find no significant impact of ADU legalization on property values in areas affected by the policy change compared to unaffected areas. These results are robust to a number of different model specifications. Several features of Ogden’s real estate market and policy environment may also contribute to this null result including challenges in effectively prohibiting black market long-term ADU rentals in areas where they remain illegal and/or property owners using ADUs for short-term vacation rentals which is legal city-wide. These results suggest that legalizing residential ADU rentals may be an effective way to increase the supply of affordable rental housing and provide supplemental income to homeowners without negatively impacting property values.

Design and implementation of 3D strata objects registration based on LADM – A case study in Malaysia

This paper discusses 3D strata objects registration and implementation within the Land Administration Domain Model (LADM) framework in Malaysia. LADM - ISO 19152:2012 provides a conceptual description for a land administration system, including 3D strata objects registration. Standardization provides flexibility to the data model, making it easier for spatial data handling. The main concern of this research is the conceptual model which has yet to be implemented by the national authority. This research will discuss the practical pathway towards realizing LADM-based 3D strata objects registration in alignment with the jurisdictional settings in Malaysia. An accurate 3D cadastre for a property including strata has become important for the land administration system. Strata objects registration has the following aspects - parcel unit, accessory unit, common property unit, limited common property unit and land parcel. Presently, in Malaysia, all these objects’ representation is in 2D. This paper focusses on extending the representation of those strata objects to 3D. The prototype development begins with the data modelling i.e. selecting relevant object classes and extending the classes with attributes. It focuses on data conversion from an existing database i.e. strata.xml format to an open source database (i.e. PostgreSQL). The visualization and application modules will then be developed using an open source platform (i.e. QGIS). The developed prototype is able to answer all questions related to strata aspects which include ownership, share unit, Management Corporation (MC), spatial source document and strata objects. We anticipate that this work could serve as the model for other national authorities having similar land administration systems especially strata objects registration including the future Spatial Data Infrastructure (SDI) initiative in Malaysia.

AGING IN COMMUNITY: A LEGAL MAPPING ANALYSIS OF MASSACHUSETTS MUNICIPAL ACCESSORY DWELLING UNIT ZONING BYLAWS

Accessory-dwelling units (ADUs) are one alternative housing arrangement that enable older adults to remain in the home despite functional decline. Functional decline increases with age making older adults more susceptible to loosing independent housing. Involuntary relocation to institutional care can result in a decline of functional health, reduced life satisfaction, impairment of psychological well-being and increased mortality rate. The majority of older Americans (93%) wish to remain in their home for as long as possible. ADUs function to maintain, stimulate and support an older adult as a means to prevent relocation to an institution. The modified environment coupled with adaptable features maintains and supports activities of daily living (ADL) within a familiar place. Under Massachusetts law MGL c. 40A, the state gives authority to cities and towns to adopt ordinances and bylaws to regulate the use of land, buildings and structures. Restrictive zoning laws limit the ability to construct health-promoting built-environments to age-in-community. All 351 Massachusetts municipalities Accessory Dwelling Unit (ADU) zoning bylaws were coded using the ADU Friendliness Score. Once scored, the 351 municipalities were placed into four categories based off their ADU score; the four categories are poor (0-24), fair (25-49), good (50-74), and excellent (75-100). Eighty-nine municipalities (25%) are in the poor category; thirty municipalities (8.5%) are in the fair category; one hundred and eighty-five municipalities (53%) are in the good category; forty-seven municipalities (13.5%) are in the excellent category. These findings contributed to a model ADU bylaw specific for aging Americans for municipalities to adopt.

The Na+ -coupled glucose transporter SGLT2 interacts withits accessory unit MAP17 invitro and their expressions overlap in the renal proximal tubule.

Na+ -glucose cotransporter 2 is the renal Na+ -coupled glucose transporter responsible for the tubular glucose reabsorption, while MAP17 was recently identified as its accessory unit. Mutations in either of the proteins' coding genes, SLC5A2 and PDZK1IP1, lead to urinary glucose excretion. To investigate whether MAP17 interacts with SGLT2 invitro, we engineered a V5-tagged SGLT2 construct and evaluated HEK293T cells coexpressing it together with a HA tagged MAP17 construct. MAP17 is shown to colocalize and coimmunoprecipitate with SGLT2. Also, in human kidney sections, the expression of both proteins overlaps at the apical surface of tubular epithelia. This interaction provides the rationale behind SGLT2 activation by MAP17 as well the similarity of the SLC5A2 and PDZK1IP1 glucosuric phenotypes.

Fourier Transform Infrared Spectroscopy and Photoacoustic Spectroscopy for Saliva Analysis

Saliva provides a valuable tool for assessing oral and systemic diseases, but concentrations of salivary components are very small, calling the need for precise analysis methods. In this work, Fourier transform infrared (FT-IR) spectroscopy using transmission and photoacoustic (PA) modes were compared for quantitative analysis of saliva. The performance of these techniques was compared with a calibration series. The linearity of spectrum output was verified by using albumin-thiocyanate (SCN(-)) solution at different SCN(-) concentrations. Saliva samples used as a comparison were obtained from healthy subjects. Saliva droplets of 15 µL were applied on the silicon sample substrate, 6 drops for each specimen, and dried at 37 ℃ overnight. The measurements were carried out using an FT-IR spectrometer in conjunction with an accessory unit for PA measurements. The findings with both transmission and PA modes mirror each other. The major bands presented were 1500-1750 cm(-1) for proteins and 1050-1200 cm(-1) for carbohydrates. In addition, the distinct spectral band at 2050 cm(-1) derives from SCN(-) anions, which is converted by salivary peroxidases to hypothiocyanate (OSCN(-)). The correlation between the spectroscopic data with SCN(-) concentration (r > 0.990 for transmission and r = 0.967 for PA mode) was found to be significant (P < 0.01), thus promising to be utilized in future applications.

Two-dimensional Ni(OH)2 nanoplates for flexible on-chip microsupercapacitors

On-chip microsupercapacitors (MSCs) compatible with on-chip geometries of integrated circuits can be used either as a separate power supply in microelectronic devices or as an energy storage or energy receptor accessory unit. In this work, we report the fabrication of flexible two-dimensional Ni(OH)2 nanoplates-based MSCs, which achieved a specific capacitance of 8.80 F/cm3 at the scan rates of 100 mV/s, losing only 0.20% of its original value after 10,000 charge/discharge cycles. Besides, the MSCs reached an energy density of 0.59 mWh/cm3 and a power density up to 1.80 W/cm3, which is comparable to traditional carbon-based devices. The flexible MSCs exhibited good electrochemical stability when subjected to bending at various conditions, illustrating the promising application as electrodes for wearable energy storage.

Immunity to the vacuolar ATPase complex accessory unit ATP6S1 in patients with malignant melanoma.

The augmentation of high-titer antibodies to ATP6S1 is associated with favorable clinical outcomes in patients who received vaccination with autologous, irradiated tumor cells engineered to secrete GM-CSF and allogeneic bone marrow transplantation. Cellular immune responses to ATP6S1 are unknown. To define its role as an immune target, examination of cellular responses to ATP6S1 and immunity related to current therapies such as checkpoint blockade is needed. We used an overlapping peptide library representing the full-length ATP6S1 protein to screen for cellular responses from the peripheral blood of patients with stage III and IV melanoma. Reactive peptide pools were used to determine the individual peptide activity and epitopes. Recombinant ATP6S1 protein was used in an ELISA to assess potential correlation with humoral immune responses and changes in immunity related to CTLA-4 blockade with ipilimumab in these patients. We observed a broad array of CD4(+) and CD8(+) cellular responses against ATP6S1, including the identification of several MHC class I and II ATP6S1 epitopes. The generation of specific CD4(+) and cytotoxic T cells revealed potent functional capability elicited by ipilimumab treatment in patients with metastatic melanoma, which revealed potent functional capability, including cytokine production, proliferation responsiveness to melanoma cell lines, and tumor-cell killing. Furthermore, the augmented humoral immune responses to ATP6S1 as a function of ipilimumab treatment were associated with beneficial clinical outcomes. These results support the continued development of ATP6S1 as a biomarker and therapeutic target.

Control Techniques for Accessory Power Unit Employed in Hybrid Electric Vehicle to Reduce the Torque Pulsations and Vibrations

A multilevel inverter is a power electronic Accessory Power Unit (APU) built to synthesize a desired AC voltage from several levels of DC voltages. Hybrid Electric Vehicles (HEVs) work through a combination of an internal combustion engine, a bank of batteries, and an electric motor. In fact, the concept is so advantageous that several major drives manufacturers have obtained recent patents on APU and associated switching techniques. For this reason, the investigation of methods to increase the reliability of APU is of high interest. It is evident that the multilevel concept will be a prominent choice for power electronic systems in future years. This paper proposes a comparison between different switching strategies for APU, based on Sinusoidal Pulse Width Modulation (SPWM) and Space Vector Modulation (SVM). The work strives hard to present the scrutiny that has been made between different open loop Pulse Width Modulation (PWM) control techniques for multilevel based APU. The comparison is made in terms of Total Harmonic Distortion (THD), switching frequency, fundamental and harmonic RMS of the voltage and current. The quality of output waveforms eliminates the torque pulsations and hence the vibrations of the electrical drive, which is a critical parameter for the smoothness of HEVs.

Upregulation of Glutamatergic Receptor-Channels is Associated with Cross-Modal Reflexes Encoded in Barrel Cortex and Piriform Cortex

Associative learning is essential for cognitions. To better understand the mechanisms underlying associative learning, we examined whether the association of two signals induces a process that one signal evokes a recall of another signal, or turned around, and how glutamatergic receptor-channels are regulated to be involved in this reciprocal information retrieval (cross-modal reflex). In our mouse model, the two sensory systems, whisker-to-barrel cortex and olfaction-to-piriform cortex, were associatively activated by simultaneously stimulating whiskers and olfaction. This training procedure for 2 weeks led to odorant-induced whisker motion and whisker-induced olfaction responses. After this cross-modal reflex onset, the barrel and piriform cortices connected each other. Local filed potentials in vivo showed that the neurons in both barrel cortex and piriform cortex turned into processing whisker signal and odor one, respectively. The activity patterns of these cortical neurons in response to whisker signal and odorant one were distinct. These results indicate that the associative activation of barrel cortex and piriform cortex makes network neurons being able to store both whisker and odor signals as well as to recognize their differences through distinct encodings. With this reciprocal information retrieval, either of two associated signals can induce two responsive behaviors for well-organized cognitions and responses to environmental alerts. In terms of synaptic plasticity, we found that excitatory postsynaptic currents mediated by ionotropic glutamatergic receptor-channels in pyramidal neurons were upregulated in their amplitudes and frequency. By genome-wide sequencing, we observed that the upregulations of neuropilin (NMDAR accessory unit), AMPAR1 precursor, neuroligin 1∼3 and tyrosine kinase in these cortical areas were associated with the cross-modal reflex and glutamate receptor-channel upregulation. [Supported by National Basic Research Program (2013CB531304 and 2011CB504405) as well as Natural Science Foundation China (30990261 and 81171033) to JHW].

The Flex-Nest: The Accessory Dwelling Unit as Adaptable Housing for the Life Span

ABSTRACTAmerican families have dramatically changed over the past sixty years, but the single-family home that houses them has evolved very little. Demographics indicate that while household numbers have gotten smaller over the decades, house sizes have become considerably larger. There has been little diversity offered in housing types, with builders and consumers favoring the detached single-family home as the icon of American success. But overwhelming recessionary pressures on American housing since 2007 have taken a toll. The housing market collapse has led to many foreclosures and subsequent vacant single-family homes, while simultaneously creating a scarcity in the rental market. Rising unemployment has seen Generation Y college graduates flocking back to the nest of their parental homes, baby boomer parents wonder when their nest will become less crowded, and the elderly are desperately trying to remain in their homes. The stock of affordable US housing is shrinking, and little new construction is on the horizon. These realities have led to a shortage of affordable housing, and motivated residents to choose complex housing arrangements, including shared housing, doubling up, and accessory dwelling units (ADUs). The ADU is examined for the financial, social, and personal benefits it can provide as an alternative to families living alone in single-family homes. For many, the partitioning of a home can provide solutions to housing children, parents, and also renters who might generate extra income to help with the mortgage. The additional benefits of ADUs for the rapidly growing elderly population are investigated, and seven flexible design models proposed as potential housing solutions.

Biomechanical validation of upper extremity exercise in wheelchair users: design considerations and improvements in a prototype device

Purpose. To develop guidelines for proper exercise execution on a novel device and to recommend design changes to the device based on biomechanical data and user feedback.Method. Seven manual wheelchair users were instructed on proper exercise technique with a novel device, which allows a person to complete a seated row. Kinematics and kinetics of the dominant upper limb and trunk were measured with motion capture and electromyography data were collected on selected muscles.Results. All subjects were able to exercise on the device with a mean power of 21.3 W (SD 7.1 W). Subjects did not keep the elbows close to the trunk during the drive phase of the row; rather, they moved from mean 75° (SD 12°) shoulder flexion to mean 62° (SD 11°) shoulder abduction. Identified problems included difficulty gripping the hand grips and user stability within the wheelchair.Conclusions. The accessory unit should be adjustable to accommodate a wide range of user sizes and abilities. Proper exercise execution is important to maximise the potential benefit and minimise risk of injury. When executed properly, this exercise may benefit wheelchair users by improving cardiovascular fitness and strengthening muscle groups linked to the reduction of shoulder pain.

Palmaris profundus: One name, several subtypes, and a shared potential for nerve compression

The palmaris profundus is a rare, but known anatomic variation which may lead to compression of the median nerve and/or its branches. Two patients with carpal tunnel syndrome are presented in whom a palmaris profundus was discovered at operation. In these cases, median nerve compression at the wrist was attributed to the course of the extra tendon and its local mass effect on the nerve (i.e., the palmaris profundus and median nerve shared a common sheath); more commonly, the resultant decreased available space for the median nerve within the carpal tunnel due to the presence of an accessory (10th) flexor tendon is thought to be responsible. Postoperative 3 Tesla magnetic resonance imaging (MRI) was performed to demonstrate the full course of the variant muscle; despite variations in the size and longitudinal extent of the accessory musculotendinous unit, an important similarity was noted: the intimate relationship of the median nerve and the palmaris profundus. These two cases and our review of the literature highlight the fact that one name (i.e. palmaris profundus) reflects several anatomic subtypes. However, the close relationship of the palmaris profundus with the median nerve in the forearm and the palm is a common theme which emphasizes the potential pathoanatomic consequences of this relationship: nerve compression.

Supernumerary left intrarenal kidney: An interesting case report and review of literature

Supernumerary kidney is a rare congenital anomaly. It is an accessory renal unit with its own blood supply and collecting system. Ectopic kidney is common and can be found in different abnormal locations. We present a rare case of small supernumerary kidney on the left side within a normal left kidney detected on investigation of urinary tract infection.

CyclicAMP and glucocorticoid responsiveness of the rat carbamoylphosphate synthetase gene requires the interplay of upstream regulatory units

Many genes involved in metabolic processes are regulated by glucocorticoids and/or cyclicAMP. The hepatic expression of the urea cycle enzyme carbamoylphosphate-synthetase-I gene (CPS) is regulated at the transcriptional level by both factors. Here, we report that the 5′ half of the distal enhancer is necessary and sufficient for full cyclicAMP responsiveness. The cyclicAMP-responsive element (CRE), and FoxA- and C/EBP-binding sites are indispensible for cyclicAMP responsiveness, indicating that these elements make up a cyclicAMP-responsive unit (CRU). In addition to this CRU, the CPS regulatory regions contain two glucocorticoid-response elements (GRE): one in the 3′ region of the distal enhancer and one in the proximal enhancer. In presence of the cyclicAMP-responsive region in the distal enhancer, only one of the GREs is required for glucocorticoid-inducible CPS expression, with both GREs acting in an additive fashion to fully confer the inducing effect of glucocorticoids. In contrast, the simultaneous presence of both GREs is required in the absence of the cyclicAMP-responsive region. In this configuration, the distal GRE fully depends on its neighbouring FoxA and C/EBP REs for activity and is, therefore, a glucocorticoid-responsive unit. In conclusion, we show here that the CPS CRU is a bifunctional unit that elicits the cyclicAMP response and, in addition, functions as a glucocorticoid accessory unit to establish a glucocorticoid response from otherwise silent proximal or distal GRUs. Therefore, cyclicAMP and glucocorticoid pathways can induce CPS transcription via overlapping sets of response elements.