WO2013043990A1

WO2013043990A1 - Organism depletion and water cleansing through acoustic techniques

Info

Publication number: WO2013043990A1
Application number: PCT/US2012/056515
Authority: WO
Inventors: Szabolcs Marka; Imre Bartos; Zsuzsanna Marka
Original assignee: Columbia University in the City of New York
Current assignee: Columbia University in the City of New York
Priority date: 2011-09-21
Filing date: 2012-09-21
Publication date: 2013-03-28
Anticipated expiration: 2014-03-21

Abstract

A method and apparatus for depleting target organisms in a container of water includes ensonifying the container of water with low intensity sound at one or more ultrasound frequencies for a duration sufficient to deplete at least 90% of the target organism.

Description

ORGANISM DEPLETION AND WATER CLEANSING THROUGH ACOUSTIC

TECHNIQUES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims benefit of Provisional Appln. 61/537,569, filed September 21, 2011, the entire contents of which are hereby incorporated by reference as if fully set forth herein, under 35 U.S.C. § 119(e).

BACKGROUND OF THE INVENTION

[0002] Aedes aegypti, an anthropophilic mosquito that is the principal vector of dengue viruses, among others, uses large man-made water containers around households as breeding sites [6]. These still water containers provide ideal locations for the mosquito larvae, and their location in the vicinity of humans greatly facilitate the newly hatched mosquitoes to quickly find hosts and spread dengue in an explosive manner. The regular treatment or cleaning of such containers is laborious [6], may involve toxic chemicals, and is often omitted. Potentially, hundreds of thousands or millions of containers should be kept clean continuously to eradicate such disease.

SUMMARY OF THE INVENTION

[0003] Techniques are provided for depleting target organisms in a container of water by ensonifying the container of water with low intensity sound at one or more ultrasound frequencies for a duration sufficient to deplete at least 90% of the target organism.

[0004] Still other aspects, features, and advantages of the invention are readily apparent from the following detailed description, simply by illustrating a number of particular embodiments and implementations, including the best mode contemplated for carrying out the invention. The invention is also capable of other and different embodiments, and its several details can be modified in various obvious respects, all without departing from the spirit and scope of the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:

[0006] FIG. 1 is a block diagram that illustrates an apparatus for ensonifying a container of water, according to an embodiment;

[0007] FIG. 2 is a flow diagram that illustrates a method for depleting a target organism in one or more containers of water, according to an embodiment;

[0008] FIG. 3A is a photograph that illustrates example Anopheles gambiae larvae before high frequency acoustic (HFA) exposure, according to an embodiment;

[0009] FIG. 3B is a photograph that illustrates an example acoustic actuator inside of a low cost ultrasound cleaner before use, according to an embodiment;

[0010] FIG. 3C is a photograph that illustrates example Anopheles gambiae larvae destroyed by HFA exposure; collected and ready for counting/archival, according to an embodiment;

[0011] FIG. 4 is a diagram that illustrates an example apparatus collecting renewable energy for days for use in an HFA burst lasting for seconds or longer, according to an embodiment;

[0012] FIG. 5A and FIG. 5B are diagrams that illustrate an example handheld apparatus (rechargeable through renewable or traditional means) transported between locations and used for a short period of time on natural stands of water, according to an embodiment;

[0013] FIG. 6 is a diagram that illustrates an example handheld apparatus transported between locations and used for a short period of time on man-made stands of water, according to an embodiment;

[0014] FIG. 7A, FIG. 7B and FIG. 7C are photographs that illustrate example larvae- infested standing water from a ditch in an African country;

[0015] FIG. 8A is a photograph that illustrates an example experimental apparatus with a subsample of water from the dish depicted in FIG. 7C before ensonification, according to an embodiment; [0016] FIG. 8B is a photograph that illustrates an example experimental apparatus with a subsample of water from the dish depicted in FIG. 7C at onset of ensonification, according to an embodiment;

[0017] FIG. 9 is a photograph that illustrates an example result after prolonged ensonification depicted in FIG. 8B, according to an embodiment; and

[0018] FIG. 10 illustrates a chip set upon which a portion of an embodiment of the invention may be implemented.

DETAILED DESCRIPTION

[0019] A method and apparatus are described for depleting target organisms in a container of water by ensonifying the container of water with ultrasound. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring the present invention.

[0020] Some embodiments of the invention are described below in the context of mosquito larvae as the target organism. However, the invention is not limited to this context. In other embodiments other water-borne organisms, alone or in combination, are the target organism. For example, various species of disease vectors and infectious agents, including Aedes aegypti, Aedes albopictus, Aedes polynesiensis, Aedes cinereus, Aedes vexans, Anopheles gambiae, Anopheles punctipennis, Anopheles quadrimaculatus, Anopheles stephensi, Anopheles walker, Coquillettidia perturbans, Culex erraticus, Culex pipiens, Culex restuans, Culex tarsalis, Culex territans, Culiseta inornata, Haemagogus mosquitoes, Ochlerotatus canadensis, Ochlerotatus dor sails, Ochlerotatus fitchii, Ochlerotatus sollicitans, Ochlerotatus triseriatus, Ochlerotatus trivittatus, Orthopodomyia signifera, Psorophora ciliata, Psorophora cyanescens, Toxorhynchites, Culiseta alaskaensis, and Simulium damnosum live at least parts of their life cycles (e.g., as larvae) in water and are therefore prime targets for ultrasonic treatments as described herein.

[0021] As used herein, a container is any limited size natural or manmade depression or vessel in which water collects and stands, including puddles, pots, barrels and drums.

Ultrasound and high frequency acoustics (HFA) each refer to pressure waves in gas, fluid or solid at frequencies above about 15,000 hertz (1 hertz = 1 cycle per second; 1 kilohertz, kHz, = 10³ Hertz).

[0022] The life cycles of some pests, such as mosquitoes or some amoebae, are closely connected to natural or artificial containers of still water, such as household water vessels and tanks, or puddles. Such containers are important targets for eradication efforts. There is a growing interest in going beyond chemicals, biological agents, and toxins and step into the high-tech field for pest control.

[0023] It has been shown that acoustic vibrations above the kiloHertz frequencies can destroy organisms, therefore cleanse water and potentially mitigate disease transmission. Thus ultrasound is an efficient, low-cost, environmentally friendly mechanism that can be lethal to various organisms in water [1-5].

1. Overview

[0024] A set of viable ultrasonic devices are described to efficiently rid from such water containers organisms such as mosquito larvae, amoebae or other animals or plants using accessible and robust acoustic technology, modified, in some embodiments, for this purpose.

[0025] FIG. 1 is a block diagram that illustrates an apparatus 100 for ensonifying a container of water, according to an embodiment. The apparatus 100 includes a waterproof acoustic actuator 101 (also called a sonicator herein) capable of transferring HFA energy into water. The apparatus also includes a power source 105 to drive the actuator sufficiently to transfer enough energy to deplete a population of target organisms, such as mosquito larvae. In some embodiments, the power source includes a chemical battery, a fuel cell, a gravity drive, or a solar panel or some other source of renewable energy. In the illustrated embodiment, the actuator 101 and power source 105 are monitored or controlled or both by a processor 103, such as a digital microprocessor or analog electronic circuit. In some embodiments, the processor is controlled by a user interface 107, such as an analog button or trigger or a digital interface, such as a graphical user interface on a touch screen, or a remote controller and a radio receiver.

[0026] Although processes, equipment, and data structures are depicted in FIG. 1 as integral blocks in a particular arrangement for purposes of illustration, in other embodiments one or more processes or data structures, or portions thereof, are arranged in a different manner, on the same or different hosts, in one or more databases, or are omitted, or one or more different processes or data structures are included on the same or different hosts. [0027] FIG. 2 is a flow diagram that illustrates a method 200 for depleting a target organism in one or more containers of water, according to an embodiment. Although steps are depicted in FIG. 2 as integral blocks in a particular order for purposes of illustration, in other embodiments, one or more steps, or portions thereof, are performed in a different order, or overlapping in time, in series or in parallel, or are omitted, or one or more additional steps are added, or the method is changed in some combination of ways.

[0028] In step 203 the ultrasound actuator is placed in position within a container of water. For example, actuator 101 of apparatus 100 is placed at a first depth in a water storage barrel.

[0029] In step 205, it is determined whether a condition predicate is satisfied to ensonify the container. For example, in some embodiments, it is determined that the user has pressed a button or trigger or other active area of the user interface 107. In other embodiments, it is determined in processor 103 that sufficient time has elapsed since the last ensonification that the target organism population has recovered enough to again be subjected to depletion for any programmed reason. For example, several days after a container is ensonified to deplete mosquito larvae, it is time to ensonify the container again. In other embodiments, the condition predicate for ensonification is triggered by other conditions, such as reaching sufficient stored power level; a sensor measuring some environmental property achieves a threshold signal level; a wireless transmission is received; the sonicator becomes immersed; or some combination.

[0030] If it is determined in step 205 that a condition predicate to ensonify is not satisfied, then in step 207 a wait ensues until a later time. For example, the processor counts multiple clock cycles in some embodiments. In some embodiments, a human operator ceases to operate the apparatus for a while. Control then passes back to step 205.

[0031] If it is determined in step 205 that it a condition predicate to ensonify is satisfied, then control passes to step 211. In step 211, it is determined whether there is sufficient power to ensonify the container in order to deplete the population of the target organism. For example, in some embodiments, it is determined that the battery level is sufficient, or that a solar panel has accumulated sufficient charge on a charge storage capacitor to drive the actuator at designed power levels.

[0032] If it is determined in step 211 that there is not sufficient power, then in step 213 a power recovery process is executed. For example, an indication of low power is presented at the user interface 107, and a wait ensues until the power is recharged, e.g., by allowing the solar panel to further accumulate charge on the capacitor or to replace or recharge a battery. Control then passes back to step 211.

[0033] If it is determined in step 211 that the power level is sufficient, then control passes to step 221. In step 221, a volume of water around the actuator is ensonified at sufficient power and duration to deplete the population of the target organism. For example, a volume is ensonified with 35 Watts at 42,000 Hz for ten seconds to deplete 94% of the mosquito larvae, as demonstrated in the experimental embodiment described below.

[0034] In step 231, it is determined if the actuator should be moved to another location, e.g., to another depth in the container, or to another natural or man-made container. If so, control passes back to step 203 to position the actuator again. If not, control passes to step 233.

[0035] In step 233, it is determined whether the process at the current location is complete. For example, it is determined whether the container is empty of water or the device 100 is due to be taken out of service. If so, then the process ends. If not, then control passes back to step 205 to determine whether it is time to ensonify again, and following steps, as described above.

2. Example Embodiments

[0036] According to an experimental embodiment, 35 Watts per liter is more than sufficient power to deplete mosquito larvae population by 94% in ten seconds.

[0037] Anopheles gambiae larvae of varying ages were used to study the biological effect of relatively low intensity («35 W/l) ultrasonic vibrations (about 42 kHz) at very short exposure times, between 1 second and 60 seconds. The observed mortality rate of larvae was stunning: 1 second of ultrasonic exposure produced -70% immediate mortality;

5 seconds of ultrasonic exposure produced -84% immediate mortality;

10 seconds of ultrasonic exposure produced 94% immediate mortality;

60 seconds of ultrasonic exposure produced 94% immediate mortality.

[0038] A control group received the same treatment except that the acoustic actuator was not turned on. This group survived the experiment. However, even a small duration of ultrasound was enough to kill the larvae with high efficiency. These results indicate that even lower power ultrasound can be effective, and durations on the order of seconds are sufficient to eradicate the pests. Higher mortality rates are expected at all duration with the use of multiple ultrasonic frequencies to attack a wider range of larval sizes.

[0039] FIG. 3A is a photograph 300 that illustrates example Anopheles gambiae larvae 310 before high frequency acoustic (HFA) exposure, according to an embodiment. FIG. 3B is a photograph 320 that illustrates an example acoustic actuator 330 inside of a low cost ultrasound cleaner before use, according to an embodiment. FIG. 3C is a photograph 340 that illustrates example Anopheles gambiae larvae 350 destroyed by HFA exposure; collected and ready for counting/archival, according to an embodiment.

[0040] Due to reflections from container boundaries, a significant part of the power remains in the water within the container, in some embodiments. It is observed that, for cleaning purposes, the sonicator is just hung at a barrel wall and it covers the full volume of the barrel. It is expected that reduced intensity, improved geometry and varying/multiple frequencies can produce even better results. A small well-made commercial acoustic actuator that is part of an ultrasound cleaner from Chicago Electric Power Tools was used effectively in this experiment. The retail cost of the device is on the order of $30, thus making the actuator affordable in large numbers to protect a wide area, with additional savings possible from mass production economies of scale.

[0041] The short exposure duration and low power consumption already indicates that low cost devices that harvest renewable power (e.g., solar cells) for days and expend their power a few times a week during ensonification events are viable and effective. [0042] In some embodiments, an ultrasonic device is permanently placed in water containers and automatically activates on a periodic basis to kill mosquito larvae and potentially other troublesome biological agents in the container. If used against mosquitoes, it is sufficient if the device needs to activate a few times during the mosquito's larva cycle (e.g., a few times a week). The device can be charged by locally available cheap renewable sources, e.g. a small connected solar panel, that provide sufficient charging capacity that enough power is saved for the short duration of activation (order of seconds) after a long collection time frame (order of days). Naturally, pools, fountains, and other common still bodies of water in the United States and worldwide can also be equipped by (more sophisticated) versions of these devices to keep our neighborhoods mosquito free and, simultaneously, chemical/poison free.

[0043] FIG. 4 is a diagram 400 that illustrates an example apparatus collecting renewable energy for intervals of minutes to days for use in an HFA burst lasting for seconds or minutes, according to an embodiment. It can be quite efficient and affordable. Solar panel cells 405a, 405b mounted outside each of two water containers 410a, 410b, respectively, collect solar energy for powering an ultrasound acoustic actuator, such as actuator 401 in container 410a.

[0044] In some embodiments, a handheld ultrasonic device (e.g., disposed in a walking cane shaped body) is transported between locations of water containers or puddles and is used for a short period of time (order of seconds to minutes) at each container to clean it from the undesirable organisms, e.g. mosquito larvae. The device can be used in regions where a person can supervise an area by commuting or walking to the sites of small water containers (puddles, water tanks, etc) and clean them one-by-one using the same device. Since it is sufficient to touch and treat each body of water only a few times a week, this can be a cost effective solution at places where human effort is more affordable than solar panel technology or high human traffic provides targets of opportunity at little incremental cost. In some embodiments, a related device [7] may be modified for such a use.

[0045] FIG. 5A and FIG. 5B are diagrams 500, 520, respectively, that illustrate an example handheld apparatus 502 with actuator 501 at one end and user interface 507 at the user's hand on the other end. This device 502 is transported between locations and used for a short period of time on natural stands of water, according to an embodiment. FIG. 6 is a diagram that illustrates an example handheld apparatus transported between locations, which is used for a short period of time on man-made stands of water, according to an embodiment. Because it is sufficient to touch each body of water only a few times a week for a few seconds each time, this device can offer a cost effective solution at places where human effort is more affordable than solar panel technology or high human traffic provides ample targets of opportunity.

[0046] Example problem in global health that can be solved or mitigated through such ultrasound devices and methods include Aedes aegypti, an anthropophilic mosquito that is the principal vector of dengue viruses. Potentially, hundreds of thousands or millions of containers should be kept clean continuously to eradicate the disease.

[0047] In another experimental embodiment, a small ultrasonic device is used to deplete organisms in a water sample retrieved from a targeted geographic locale. FIG. 7A, FIG. 7B and FIG. 7C are photographs that illustrate example larvae-infested standing water from a ditch in an African country used in an experiment, according to an embodiment. FIG. 7A is a photograph 701 that illustrates an example urban drainage ditch 705 that provided a water sample. The ditch 705 contains standing water 706. A water sample was selected at a random from this stagnant urban drainage ditch in Africa. There were larvae of multiple insect species in the water beyond the larvae of (unidentified) mosquitoes of varying ages. FIG. 7B is a photograph 702 that illustrates an example close-up of standing water 706. Evident are multiple larvae 707. FIG. 7C is a photograph 703 that illustrates an example close-up of a dish 710 that contains a water sample 720 from the standing water 706. Evident are multiple larvae 730 that all appear alive because they become active when the dish 710 is shaken manually.

[0048] FIG. 8 A is a photograph 801 that illustrates an example experimental apparatus 810 with a subsample 820 of water from the dish 710 depicted in FIG. 7C before

ensonification, according to an embodiment. The example experimental apparatus 810 used was a Codyson Ultrasonic Contact Lens Cleaner manufactured commercially by SHENZHEN CODYSON ELECTRICAL CO., LTD. of Guangdong, China. It is a simple low power sonicator that was connected to a wall power outlet via a plug-in power converter. This apparatus 810 ensonifies a volume in fluid container 812 of about 10 cubic centimeters (equal to 10 milliliters). The ensonification is delivered at 120 kHz consuming power of about 7 watts per duty cycle and delivering a small fraction of that as sound wave power on each duty cycle of multiple duty cycles. This amounts to a power level of much less than 0.7 watts per milliliter, or 700 milliwatts per milliliter. A subsample 820 of water from dish 710 with larvae 820 was placed into the fluid container 812. Photograph 801 was taken Sunday, January 08, 2012, 8:50:37 AM Eastern Standard Time. FIG. 8B is a photograph that illustrates the example experimental apparatus 810 with a subsample 820 of water from the dish 710 depicted in FIG. 7C during ensonification, according to an embodiment. The larvae 820 are disturbed by the ensonification, resulting in violent gyrations that cause the larvae to appear blurred in the photograph 802. Photograph 802 was taken at start of ensonification on Sunday, January 08, 2012, 8:50:40 AM Eastern Standard Time.

[0049] FIG. 9 is a photograph 900 that illustrates an example result after completion of the ensonification depicted in FIG. 8B, according to an embodiment. A sample dish 910 holds a water sample 920 discharged from the experimental apparatus 810 of FIG. 8B, after a sequence of 120 kH sonic exposures, using a duty cycle of about 50% on and about 50% off, and lasting for a total time on of less than 100 seconds. Photograph 900 was taken on Sunday, January 08, 2012, 10:41:28 PM Eastern Standard Time, several hours after treatment ended. The water sample 920 includes about thirty larvae. The states of the larvae were estimated by determining which became active in response to manually shaking the dish 910. About five larvae appear alive. Two larvae 931 appear alive without severe visible bodily damage; and, three larvae 933 appear alive but show severe bodily damage. The remaining larvae 935 appear dead. Assuming a total of 26 larvae in the water sample, this amounts to about 80% killed and 12% severely damaged, for a total of 92% depleted and about 8% survival. Even without any attempts at optimization, a depletion rate over 90% is achieved.

[0050] The example embodiments demonstrate that effective cleansing of standing water occurs by ensonifying the standing water in an acoustic frequency range from about 40 to about 120 kHz in a power concentration range from about 35 to 700 milliwatts per milliliter (mW/ml) for a duration in a range from about 1 to about 100 seconds.

[0051] In some embodiments, relative power pulsing and time structure are chosen to achieve desired efficiency for one or more species. For example, to enhance efficacy against one or more target species of larvae, rather than emitting long duration pulses at one power level, low power is emitted in pulses or continuously to make the target species move continuously, then an occasional very short higher power blast at random times is emitted.. The high blast is effective at killing in constructive interference nodes of the vibration pattern; and, the low power at the same or different frequency is used to excite the larvae to move out of a null point in the vibration pattern. It is anticipated that one of ordinary skill in the art can adjust frequency, power, exposure time and sweep rates through routine experimentation to achieve any desired depletion rate in any volume of standing water.

[0052] In various embodiments, the waterproof acoustic actuator 101 is configured to emit one or more ultrasonic frequencies in a range from about 30 kHz to about 1000 kHz. In another set of embodiments, the waterproof acoustic actuator 101 is configured to emit multiple frequencies in a range from about 40 kHz to about 120 kHz. Example acoustic

TM

actuators include TX517 from TEXAS INSTRUMENTS of Dallas Texas, which is a fully integrated, dual channel, high voltage Transmitter with control logic. Submersible ultrasonic

TM

transmitters include CLANGSONIC CN120-1800, a 40/120 kHz 1800 Watts submersible

TM

transducer, CLANGSONIC CN28-2000, a 28 kHz 2000 Watts submersible transducer,

TM

and CLANGSONIC CN120-1600, a 120 kHz 1600 Watts submersible transducer, all

TM

available from YUHUAN CLANGSONIC ULTRASONIC TRANSDUCER CO., LTD of Zhejiang, China. Other candidate ultrasonic transducers include the JTM-1040 Industrial Ultrasonic Cleaner 28 kHz and 40 kHz at 2000 Watts, available from SKYMEN CLEANING

TM TM

EQUIPMENT SHENZHEN CO., LTD. of Guangdong China; and COSSON KS- A1440H09TR-W1 40 kHz from DONGGUAN COSSON ELECTRONIC PLASTIC CO., LTD.™ of Guangdong China. [0053] In various embodiments, the power source 105 is a battery pack, a fuel cell or a solar power cell, such as a photovoltaic cell, a capacitor, or any other suitable renewable or traditional power source, such as shaking from traffic or animal movement or wind or water wheel, which is adequate at these power levels, alone or in some combination. Several

TM

commercial solar cells are available from FUTURLEC of New York City, New York,

_3

such as 0.5 volt (V), 280 milliAmpere (mA, 1 mA=10 Amperes) High Efficiency Miniature Solar Cell, Part Code: SZGD6030, available at time of this writing for about 1.5 US dollars, which offers high-current output, ideal for use in low-voltage applications and battery chargers. In some embodiments, this solar cell is combined in series or parallel arrangements

TM

for increased voltage or current. Also available from FUTURLEC is a 6.0 V 16 mA High Voltage Miniature Solar Cell, Part Code: SZGD5020, also available at time of this writing for about 1.5 US dollars, which is ideal to replace 6V battery packs or equivalent loads. Can be combined in series or parallel arrangements for increased voltage or current. Ideal for use

TM

with motors or other solar products. Also available from FUTURLEC is a 9.0 V 70 mA Solar Cell, Part Code: SZGD8569, available at time of this writing for about 6 US dollars. Solar collection panels for all of the above commercial products are less than about 10

_2

centimeters (cm, 1 cm =10 meters) by 10 cm in area.

[0054] Rechargeable battery packs to be used in power source 105 with the solar cell or independently are commercially available, such as 1500 eneloop 4 Pack AA Ni-MH Pre-

TM

Charged Rechargeable Batteries with Charger from SANYO of PANASONIC

TM

CORPORATION OF NORTH AMERICA in Secaucus, New Jersey. Other suitable

TM

batteries and chargers are available from OPTIMA Batteries, Inc., of Milwaukee

Wisconsin. In some embodiments, ultracapacitors are used to store and discharge energy very quickly. Ultracapacitors are commercially available, e.g., from MAXWELL

TM

TECHNOLOGIES, INC. of San Diego, California. Various solar charge

controllers/battery chargers are available commercially, e.g., from SUNFORCE

PRODUCTS INC. of Montreal, Canada. [0055] Programmable microprocessors to serve as processor 103, are available commercially, and are programmed or otherwise configured to control power management and duty cycle times. In some embodiments, the device is controlled manually and processor 103 is omitted. Example commercially available programmable microprocessors to serve a s

TM

processor 103 include K10_120: KINETIS K10 Baseline 120 MHz MCUs from

TM

FREESCALE SEMICONDUCTOR INC. of Austin, Texas. The Kinetis K10 MCU family

3

includes 512 kilobytes (kB, 1 kB = 10 bytes, 1 byte = 8 binary digits, bits) to 1 megabyte (MB, 1 MB = 10⁶ bytes) of flash memory, a single precision floating point unit, and a NAND flash controller. The Kinetis K10 family is available in 144 LQF and 144 MAPBGA packages. Another example commercially available microprocessor is DFPIC1655X - RISC Microcontroller from Digital Core Design of Bytom, Poland. In some embodiments, the processorl03 is a mass produced, custom-designed, small footprint, low cost and low energy

TM

controller, as available for example from MOSAIC INDUSTRIES INC. , of Newark California.

[0056] Keypads with small liquid crystal display suitable as a user interface 107 are commercially available. For example, custom silicone rubber keypads and conductive rubber

TM

keypads can be ordered from NORTHPOINT TECHNOLOGIES, INC. of El Paso, Texas. Standard and custom LCD displays can be ordered from PHOENIX DISPLAY

TM

INTERNATIONAL, INC. of Tempe Arizona. 3. Processor Hardware Overview

[0057] In some embodiments the processor 103 is implemented on a chip set.

Information is represented as physical signals of a measurable phenomenon, typically electric voltages, but including, in other embodiments, such phenomena as magnetic,

electromagnetic, pressure, chemical, molecular atomic and quantum interactions. For example, north and south magnetic fields, or a zero and non-zero electric voltage, represent two states (0, 1) of a binary digit (bit). Other phenomena can represent digits of a higher base. A superposition of multiple simultaneous quantum states before measurement represents a quantum bit (qubit). A sequence of one or more digits constitutes digital data that is used to represent a number or code for a character. In some embodiments, information called analog data is represented by a near continuum of measurable values within a particular range. A sequence of binary digits constitutes digital data that is used to represent a number or code for a character.

[0058] FIG. 10 illustrates a chip set 1000 upon which an embodiment of the invention may be implemented. Chip set 1000 is programmed to perform one or more steps of a method described herein and includes, for instance, the processor and memory components incorporated in one or more physical packages (e.g., chips). By way of example, a physical package includes an arrangement of one or more materials, components, and/or wires on a structural assembly (e.g., a baseboard) to provide one or more characteristics such as physical strength, conservation of size, and/or limitation of electrical interaction. It is contemplated that in certain embodiments the chip set can be implemented in a single chip. Chip set 1000, or a portion thereof, constitutes a means for performing one or more steps of a method described herein.

[0059] In one embodiment, the chip set 1000 includes a communication mechanism such as a bus 1001 for passing information among the components of the chip set 1000. A processor 1003 has connectivity to the bus 1001 to execute instructions and process information stored in, for example, a memory 1005. The processor 1003 may include one or more processing cores with each core configured to perform independently. A multi-core processor enables multiprocessing within a single physical package. Examples of a multi- core processor include two, four, eight, or greater numbers of processing cores. Alternatively or in addition, the processor 1003 may include one or more microprocessors configured in tandem via the bus 1001 to enable independent execution of instructions, pipelining, and multithreading. The processor 1003 may also be accompanied with one or more specialized components to perform certain processing functions and tasks such as one or more digital signal processors (DSP) 1007, or one or more application- specific integrated circuits (ASIC) 1009. A DSP 1007 typically is configured to process real-world signals (e.g., sound) in real time independently of the processor 1003. Similarly, an ASIC 1009 can be configured to performed specialized functions not easily performed by a general purposed processor. Other specialized components to aid in performing the inventive functions described herein include one or more field programmable gate arrays (FPGA) (not shown), one or more controllers (not shown), or one or more other special-purpose computer chips.

[0060] The processor 1003 and accompanying components have connectivity to the memory 1005 via the bus 1001. The memory 1005 includes both dynamic memory (e.g., RAM, magnetic disk, writable optical disk, etc.) and static memory (e.g., ROM, CD-ROM, etc.) for storing executable instructions that when executed perform one or more steps of a method described herein. The memory 1005 also stores the data associated with or generated by the execution of one or more steps of the methods described herein.

[0061] In the foregoing specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. Throughout this specification and the claims, unless the context requires otherwise, the word "comprise" and its variations, such as "comprises" and "comprising," will be understood to imply the inclusion of a stated item, element or step or group of items, elements or steps but not the exclusion of any other item, element or step or group of items, elements or steps. Furthermore, the indefinite article "a" or "an" is meant to indicate one or more of the item, element or step modified by the article.

References

[1] S.Z. Child, C.H. Raeman, E. Walters, E.L. Carstensen, "The sensitivity of Drosophila larvae to continuous-wave ultrasound," Ultrasound in Medicine & Biology, Volume 18, Issue 8, Pages 725-728, 1992.

[2] S.Z. Child, E.L. Carstensen, "Effects of ultrasound on Drosophila— IV. Pulsed exposures of eggs," Ultrasound in Medicine & Biology, Volume 8, Issue 3, Pages 311-312, 1982. [3] Sally Z. Child, Edwin L. Carstensen, Shung K. Lam, "Effects of ultrasound on drosophila: III. Exposure of larvae to low-temporal-average-intensity, pulsed irradation," Ultrasound in Medicine & Biology, Volume 7, Issue 2, Pages 167-173, 1981.

[4] S.B. Barnett, G.R. Ter Haar, M.C. Ziskin, W.L. Nyborg, K. Maeda, J. Bang, "Review: Current status of research on biophysical effects of ultrasound," Ultrasound in Medicine & Biology, Volume 20, Issue 3, Pages 205-218, 1994.

[5] Wesley L. Nyborg, "Biological effects of ultrasound: Development of safety guidelines. Part II: General review," Ultrasound in Medicine & Biology, Volume 27, Issue 3, Pages 301- 333, March 2001.

[6] Vu Sinh Nam, Nguyen Thi Yen, Brian H. Kay, Gerald G. Marten, And Janet W. Reid, "Eradication Of Aedes Aegypti From A Village In Vietnam, Using Copepods And

Community Participation," Am. J. Trop. Med. Hyg., 59(4), pp. 657-660, 1998.

[7] Lester Kok," Mosquitoes vanish with zapping wand," The Straits Times, Saturday, September 18, 2010, page D9.

Claims

What is claimed is: 1. A method for depleting target organisms in a container of water comprising ensonifying the container of water with low intensity sound at one or more ultrasound frequencies for a duration sufficient to deplete at least 90% of the target organism.

2. A method as recited in claim 1, wherein ensonification occurs in an acoustic frequency range from about 40 to about 120 kiloHz and in a power concentration range from about 35 to 700 milliwatts per milliliter for a duration in a range from about 1 to about 100 seconds.

3. An apparatus comprising:

a power source;

an ultrasound waterproof acoustic actuator; and

a user interface,

wherein the apparatus is configured to ensonify a container of water with low intensity sound at one or more ultrasound frequencies for a duration sufficient to deplete at least 90% of a target organism.

4. An apparatus as recited in claim 3, wherein the apparatus is configured to ensonify the container in an acoustic frequency range from about 40 to about 120 kiloHz and in a power concentration range from about 35 to 700 milliwatts per milliliter for a duration in a range from about 1 to about 100 seconds.

5. An apparatus as recited in claim 3, wherein the power source comprises a solar cell.

6. A non-transient computer-readable medium carrying one or more sequences of instructions, wherein execution of the one or more sequences of instructions by one or more processors causes an apparatus to ensonify a container of water with low intensity sound at one or more ultrasound frequencies for a duration sufficient to deplete at least 90% of a target organism.

7. A non-transient computer-readable medium as recited in claim 6, wherein the apparatus is further configured to ensonify the container in an acoustic frequency range from about 40 to about 120 kiloHz and in a power concentration range from about 35 to 700 milliwatts per milliliter for a duration in a range from about 1 to about 100 seconds.